Bra Science: A direct comparison between Ewa Michalak CH(P) & Comexim 3 part half cups

Good morning loyal readers.  As promised, I’ve worked up a massive blog post in an attempt to compare two very similar bra styles by two different Polish manufacturers.  Firstly, let’s review how each company sizes their bras:

Ewa Michalak uses the European sizing system for her band sizes, so the band numbers are done in centimeters and each size up is counted by 5.  60 = 28 band, 65 = 30 band, 70 = 32 band, etc.  She then uses the UK sizing system for her cup letters, and each cup size is scaled up by 1.”  UK cups follow the pattern of double letters, and go like this: D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, and so on.  Note there is no double E, and no letter I.

Comexim uses the European sizing system for both their bands and their cups, and each cup size is scaled up by 2cm (1″ = 2.54cm) – so slightly less depth is added per cup volume than with Ewa Michalak.  EU cups do not use double letters, and go like this: D, E, F, G, H, HH, J, K, L, M, N, and so on.  Worthy of noting:  Comexim has replaced what would be their “I” cup with a double H.  This is the only double letter they use.

Now, let’s review the concept of index sizing and sister sizing.  An index size is based on the UK sizing method and is your band size, followed by a colon, then your cup size in number of cups, starting with A = 1, that you need to count to so you have your correct cup depth.  This should somewhat align with the perimeter measurement of your breast in inches, however due to individual breast shape, scaling, and size variations between manufacturers it doesn’t always work that way.  Personally, I wear a 28FF or G, so my index size would be 28:8 or 28:9.  A 34FF would be 34:8.  A 32E would be 32:6.  Sister sizing is the process of reducing or increasing the cup letter size to maintain the same cup volume when changing band sizes.  If I take my index size of 28:9 and go up to a 30 band size, I need to subtract one from my cup volume number to maintain the same cup volume.  Since Ewa Michalak only produces 60 bands by request and charges a custom fee, I choose to wear her 65 bands and alter them tighter if needed.  To sum this up, my index size in Comexim is a 28:9, and in Ewa Michalak is a 30:8.  Due to the 2cm scaling Comexim uses, many people find they need to go up one more cup size to have adequate room since 2cm is smaller than 1 inch.  This becomes more pronounced the larger your breasts are in relation to your band size.  I can wear my UK index size in Comexim.  Some cannot.  Your mileage may vary.

On to the good stuff.  The two bras I’ve chosen to compare today are Ewa Michalak CH Biszkopty in size 65FF (30:8), and Comexim Elena 3 part half cup in size 60HH (28:9).  Remembering the rule of sister sizes, these bras should theoretically contain the same volume within a half centimeter or so – almost a negligible difference.  You’ll have to bear with me as I go over the EM’s measurements, since the band has been altered and I have moved the straps inward.  For the purposes of this little bra science project, I have measured strap placement on my EM from the original point of attachment at the cups, so my alteration doesn’t skew the results.  I picked these two specific bras because from the array of half cups I’ve tried from both brands, I feel these two bras run the most true-to-size – meaning they’re a good representation of the average volume this size should contain, without one bra being an outlier by running either big or small for its tagged size.

Let’s get some pictures going!! Let’s start with general appearance:


Ignoring the color – side by side, each bra is pretty similar.  Same general cup shape and design.  There are slight differences in the seaming pattern, which I’ll get into in a bit.

Throughout this process I made notes of what I consider to be “slight” differences -within 0.2″ or so that could potentially be chalked up to manufacturing variances and could potentially vary within the same cup style and size from the same brand, and what I consider to be significant differences – greater variations that would generally hold true regardless of which brand you’re wearing.  Moving on to measurements, starting with cup width:


I couldn’t take this measurement with one hand and shoot with the other, so I drew a line to show how I measured.  I placed the bra in a neutral position, took a soft tape measure and measured from the inner edge of the outer wire channel straight across the bra to the inner edge of the inner wire channel.

Comexim: 5.25″.
EM: 5.125″
Conclusion:  EM has narrower wires, but it’s a slight difference.

Next up is cup height:


To measure cup height, I pushed the cup inside out and measured from the top of the bottom underwire straight up the center seam to the top of the cup.

Comexim: 5.75″
EM: 5.5″
Conclusion: Comexim’s cups are taller, and it may or may not be a significant difference.

How about we look at the length of the underwires themselves:


To measure this I took the soft tape measure and curved it along the bottom of the cup, following the wire in its channel.

Comexim: 9.5″
EM: 9.5″
Conclusion: They’re identical.

The next thing I want to address is the placement of the straps on the cups themselves, and also on the band.  As in: how far apart are the straps from one another?


This is where I had to measure from the original point of attachment on my EM bra, so the arrows extend past the current strap placement.  I also placed both bras in a neutral position so the measurement was as accurate as possible.

Comexim: 9.825″
EM: 10.25″
Conclusion: Ewa’s straps are set wider, and this is quite a significant difference.  Straps being set too widely is a very common complaint about EM bras, and I was not surprised at all to find such a large variation among the two brands.

The same holds true for strap placement on the band.  To take this measurement I added an extender to my EM bra so that both bras have a stretched band measurement of 28″ and then I closed the bra band on the loosest hooks.  Again, bras in a neutral positon.


Comexim: 6.5″
EM: 8″
Conclusion:  EM’s straps are set significantly wider on the back of the bra.

I moved on to measure the distance of the vertical seams from each other at both the bottom and the top of the bra.  Placement and shape of the vertical seams will affect the overall shape the bra gives your breasts when wearing it.  Here’s the bottom:


When I did this I accidentally measured on the inside of the Comexim cup and the outside of the EM cup, but I don’t think there’s a difference on the EM if I’d done it on the inside.  The seams are where they are, regardless of which side of the cup you’re looking at.

Comexim: 0.825″ (2 cm)
EM: 0.625 (1.6 cm)
Conclusion: Ewa’s seams start closer together.

Here’s the top:


Comexim: 1.5″ (3.8 cm)
EM: 1.75″ (4.4 cm)
Conclusion: Comexim’s seams start farther apart at the bottom and follow a more parallel path up the height of the cup.  Ewa Michalak’s seams start next to each other at the bottom and follow diagonal paths away from each other towards the top of the cup.

Cup depth – the biggest factor that determines if the bra is going to contain your breasts or not. I took two cup depth measurements in an attempt to show the amount of overall projection each style has.  One across the middle of the cup, and one across the apex of the cup – the deepest point and often where one’s nipples lie.  Here’s the middle of the cup.  I measured this by placing the bra over my knee to hold its shape while measuring with the tape hugging the curve of the cup from the inner edges of one wire channel to another.  Since this was basically impossible to take pictures of, I attempted to draw a line showing the path my measuring tape took.  Use your imaginations:


Comexim: 8.125″
EM: 8.0″
Conclusion:  There’s a slight difference, but it’s almost identical.  Somebody else doing this measurement may get identical numbers.

Here’s along the apex:



Comexim: 9.0″
EM: 9.625″
Conclusion: Ewa’s cups are significantly deeper at the apex (some of this could be correlated with the 1″ vs 2cm cup scaling methods) while Comexim’s cups are generally flatter/shallower overall.

Strap width can play a role in how comfortable the bra straps are for all day pressure on your shoulders, and especially in larger bust sizes, narrower straps aren’t padded or wide enough to distribute weight evenly and can really dig into one’s shoulders:


Comexim: 0.625″
EM: 0.625″
Conclusion: They’re identical.  Strap width varies somewhat among different bra styles.  IMO, interchangeable straps should be standard on every bra ever made.  Everybody has their own tolerance level when it comes to shoulder pressure, however if your band fits snugly enough it will do 80% of the heavy lifting and support work.

Gore width is essential when it comes to comfort, as a properly fitting bra should have a tacking gore.  Different breasts are differently spaced apart on different chests, so I measured the gore width at the top and bottom of both bras, each of which are known to have narrow gores relative to UK brands.  Top:


Comexim: 0.5″
EM: 0.625″
Conclusion: Comexim is narrower.  This varies somewhat from style to style within the brand.  You can ask Comexim to make a bra with overlapping wires if the tops of gores really bother you.

I also measured the bottom width of the gore, and was somewhat surprised by the results.  I’m close set at the top and then quite splayed, and often wondered if the reason a lot if not all of my gores float somewhat at the bottom was related to their width.  I still don’t know for sure, but I measured it anyways for giggles (and accidentally covered up the numbers on the Comexim):


Comexim: 1.5″
EM: 2.125″
Conclusion:  The EM is significantly wider.  This too may vary among bra styles.  I would have sworn it would be the other way around.

While I’m at it – gore height.  This describes the measurement from the top of the center gore (the piece in the center of the bra) to the bottom of the band, from the inside:


Comexim: 2.75″
EM: 2.75″
Conclusion: It’s identical, although Comexim is willing to make a bra with a reduced gore height alteration.

One last thing – immediate projection.  Immediate projection refers to the amount of room a cup has directly above and going forward from the underwire.  For pendulous breasts like mine, this is THE BIG FACTOR in my “does it fit?” decisions.  Pendulous simply means that your breast tissue hangs down below the point of attachment (root) to your chest wall.  You can be varying degrees of pendulous – I am quite pendulous in that unsupported, my breast tissue hangs down inches below the root.  Bras that are too shallow at the underwire get pushed down my ribcage by my breasts searching for more room to settle.  There really is no foolproof way to measure this – it’s all about placing the bra in your inframammary fold (IMF) correctly, and then determining over the course of a day, hours, or even minutes if it’s really bad, if it will stay in place.  Polish bras are considered among the most immediately projected bras on the market, and the half cups – the bra styles I’m reviewing today – are considered the best of the best from each brand.  Since I can’t put it in numbers, I’m including side by side profile shots of me wearing each bra.


In each picture, there is no wrinkling or folding in the bottom of the cup – evidence that my breasts do not have enough room.  There is also no space between the underwire and my IMF.  I don’t find one brand or the other to have a significant difference in the amount of immediate projection in their half cup styles.  This too may vary slightly among bra within the brands, but I feel safe in saying that each brand’s half cup cuts are suitable for pendulous breast shapes.

One thing I would like to note:  Ewa Michalak manufactures two different padded half cup cuts – the CH and CHP, with the CHP being the dominating half cup currently produced.  In smaller sizes, they’re virtually identical.  You can check out a CHP in action in my review of theLawenda.  In larger sizes, the CHP gets notably wider and less immediately projected.  I consider myself right on the line between small band/medium bust and small band/large bust.  If I were a 65G/GG and larger volumes, I would carefully consider potential fit changes between the CH and CHP.  Comexim also produces two padded half cup cuts – one with a single vertical seam and one with the two vertical seams as shown in this post.  The single vertical seamed cups are vastly different – significantly wider and much shallower at the wire.  If your shape is like mine, I strongly consider you to request all half cup bras to be made with the 2 seamed pattern.  You can see a single seamed half cup in action in my review of the Veronique and clearly see the fit differences and why it did not work for me.

Major differences between Ewa and Comexim as manufacturers:  Ewa produces over 150 sizes of bras in a large variety of shapes and cups.  Unlined balconettes, unlined half cups, padded balconettes, padded plunges, a variety of bras engineered for small busts, bras engineered for large busts, etc.  She is hesitant if not completely unwilling to customize bras, will not consider changing her strap placement at all, and charges extra for custom band and cup sizes.  You can communicate with Ewa in English via Kaska, their customer service rep, and will receive a reply generally very quickly.  Comexim offers 2 padded styles, a plunge and a half cup, and a handful of unlined bras.  They are, however, extremely accommodating to alteration requests and will alter/customize about anything you can think of for no charge at all.  One major downside is they are currently difficult to get hold of and I’m not sure why – be it order backlog or what.  Email response is running at a snail’s pace.

WHEW.  That was quite a nerdy scientific novel I wrote there!  I hope you all enjoyed it, learned from it, and can put this experiment to the test yourselves.  Stay tuned for my upcoming reviews of my first unlined Polish bra and Ewa’s brand new CH style, the Cherry!

16 thoughts on “Bra Science: A direct comparison between Ewa Michalak CH(P) & Comexim 3 part half cups

  1. Thank you!, I’m in the process to order my first comexim bras and this was very useful.
    About Comexim sizing, I have a question, I have a very similar shape that you, but less volume and I more FOT (between FOT/Even), currently I’m wearing Cleo Maddie in 28F (I know that apparently run a little small in cups and band) I’m between 28F/28FF. Should I order a 60H or go for 60G?, I’m thinking to order the 3 HC cut (half cups 3 seams).

  2. Great post. I do this with all of my bras (on Bratabase) and have done for years. All of my bras are within 0.5 inches for each measurement and most of them are identical. My breasts are very centre deep and close set. I prefer 11.5 inches of depth at the apex.

    1. I’m on bratabase myself and always measure all my bras. I wanted to measure details way beyond what you can do on BTB, and make a post specifically comparing these two styles, mostly because I often see people complain that Comexim doesn’t make a CHP cut and really, they do – it’s very very similar overall. Both these bra styles are popular and I’m kind of neurotic and wanted to see exactly what the difference is, beyond initial price tag.

  3. Amazing! Thanks! Before I got to the end I was thinking, “I love that girlnerds have found The Bra and have begun subjecting it to scientific methods.” This was incredibly helpful.

  4. I love your review!
    Do you have any idea why Longline Halfcups are so vastly different?
    I ordered a Rose Longline (which is a 2-seamed halfcup) and was so hyped-up after your comparison, but it is much shallower, and more closed on top than EM CH 🙁

    1. I have no idea but I’ve noticed that! It’s very frustrating. I assume the only main difference is the band length so I’m not sure why that would affect the bra so much. I’ve never tried a long line, my flared ribs would NOT be happy with that!

      1. At least someone who believes me lol.
        I have flared ribs too, and I love longlines because they keep the wires from pressing too much against my ribs in my IMF.
        I just ordered a custom 3-seam-HC-Longline in Dottie fabrics, and asked them to use the regular 3-seam-HC cut and just add the longer band. No clue if they understood what I mean, but maybe I’m lucky 😀
        In any case longline Dottie will be so awesomely retro 😀

        1. Oh my gosh I would love to see a long line Dottie. I’d love to see it in black and white with red trim too, instead of blue with pink trim. Black white and red screams total pin up girl. You’ll have to post pictures of your result or link them in a comment!

          I measured my widest rib flare at 1.5-2″ wider than my snug underbust. I cannot imagine any true longline band getting along with that! I have problems with underwires pressing against my ribs if the cup is not projected enough at the wire, but I don’t have any problems if I have enough immediate projection to allow the underwires to sit very firmly in my IMF. I’ve become exceedingly picky about that fit aspect these days!

    1. Bummer! I did see that thread on ABTF and wrote you in there 🙂 I have a longline myself that I’m probably going to list. I wish they’d tweak the long line design a bit so it offered better support!

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