★★★★★Verified
+2Excellent quality at a great price. Sizing is exactly right. Already thinking about my next order. Arrived fast and I recommend the seller.
Diego R. · PeruS · Black
BSLYR / 001Structural base layer
Black · S–5XL
Black · S–5XL
The thingthat makesthe dress shirtsit right.
Built quietly · Worn under everything · The structural layer beneath your shirt
↓ Buy
Hidden · Black
Hidden · Grey
Hidden · White
Day 1 / Day 30BeforeWith BSLYR
✓Knitted-in armature
✗Generic compression
✓Holds drape all day
✗Bunches by lunch
✓Flatlock seams
✗Overlock seams
✓30-day refund
✗No warranty
★★★★★4.8 / 5
“The first base layer that actually holds my dress shirts flat all day. I don’t think about the fit anymore. That’s the point.”
Daniel S. · Verified Buyer
How it worksKnitted-in armatureFour-way stretch knitFlatlock seams
Built forWhy men keep
01Holds drape02Four-way stretch03Knit-in armature0430-day refundWhy men keep
coming back.
Free US ship · 30-day refund — try it on, decide later
4.8 (1,292 reviews)
BSLYR · Compression base layer · Black
Get rid of
Dad Bod
Dad Bod
Promotes
Weight Loss
Weight Loss
Reduces
Man Boobs
Man Boobs
Smooths
Love Handles
Love Handles
The structural layer beneath your shirt.
A four-way stretch base layer that changes the surface a shirt sits on. Worn under polos, dress shirts, and tees. Engineered to disappear once it’s on.
$34.99Single · 3-pack $69.99 · 5-pack $89.99
Ships free in the US in 5–11 business days. 30-day refund — no return required.
Most shirtsdon’t fit.They hang.
BeforeWith BSLYRA shirt is cut to drape. It pulls at the chest if you have any taper, gathers at the waist if you don’t, and goes diagonal across the shoulder by the third meeting.
Most men buy three more shirts trying to fix it. None of them do. The fix is underneath.
A four-way stretch knit set against the torso changes the surface the shirt is sitting on. Drape becomes structure. The silhouette holds. Refined for men who notice fit and don’t talk about it.
Threeengineeringdecisions.
Every choice in the construction was driven by one question: how do you make a layer that disappears under any shirt without losing structural hold through the day.
01
Four-way stretch knit.
Compresses without restricting. Holds the line from morning to last meeting.
02
Flatlock seam construction.
Smooth under woven cotton. No print-through under polos or dress shirts. Worn invisibly.
03
Knitted-in armature pattern.
Compression zones woven into the structure of the fabric, not printed on. Muted on Hidden. Cyan on Vent and Original.
Spec’dcompletely.
- Composition
- 90% polyester · 10% spandex · four-way stretch knit
- Construction
- Knitted-in armature pattern · flatlock seams · no external stitching across chest plane
- Cut
- Sleeveless · scoop neck · extended torso for stay-tucked fit
- Sizing
- Eight sizes S–5XL · sized by height + weight, not t-shirt size
- Care
- Cold machine wash · tumble dry low
- Origin
- Built & shipped from manufacturing partner · 5–11 business day delivery
Verified buyers4.8 out of 5
4.8 out of 5
from 1,292 buyers.
★★★★★4.8 / 5
+2★★★★★Verified
+1Arrived ahead of schedule. Good product quality. Tried it on — soft to the touch, snug but doesn't squeeze. Overall a great purchase.
Pablo G. · SpainS · Black
★★★★★Verified
Great shirt and fast delivery. Sits tight as expected. I'm 6'3" / 200 lbs and ordered XXL — fits perfectly.
Sebastian K. · GermanyXXL · Grey
★★★★★Verified
All good — same as the listing. Ordered two and both arrived without issue. Fabric is soft and lightweight, breathable, dries fast.
Ana L. · MexicoS · Black
★★★★★Verified
Very nice, comfortable, and excellent quality.
Giulia R. · ItalyS · Black
★★★★★Verified
Identical to the listing. Medium fits me perfectly snug as I needed. Will order more.
Carlos M. · MexicoM · Black
★★★★★Verified
Very good. Just like the listing photo. Love it — pleasant to wear.
Camille R. · FranceM · Black
★★★★★Verified
Second one I'm buying — for the quality and price. 100% recommend.
Miguel S. · MexicoM · Black
★★★★★Verified
Arrived well-packaged and before the expected date. Recommend.
María V. · SpainL · Black
Real customers
Real bodies.Real fits.
Buyers in the field, putting BSLYR on for the first time. No paid actors, no agency reels — just men in their bathrooms recording the difference the layer makes.
Don’t size by t-shirt.
| Size | Height | Weight | Chest |
|---|---|---|---|
| S | 5'6"–5'8" | 110–154 lb | 34–36" |
| M | 5'8"–5'10" | 154–198 lb | 36–39" |
| L | 5'10"–6'0" | 198–243 lb | 39–42" |
| XL | 6'0"–6'2" | 243–287 lb | 42–45" |
| XXL | 6'1"–6'3" | 287–331 lb | 45–48" |
| 3XL | 6'2"+ | 331–375 lb | 48–51" |
| 4XL | 6'2"+ | 375–419 lb | 51–52" |
| 5XL | 6'2"+ | 419–463 lb | 52–54" |
Compression fit runs ~1 size slim of standard US. Use height and weight, not your usual t-shirt size. Between two sizes, size up.
Picka layer.
$34.99One layer
$69.99Two layers, one free
Most order
$89.99Three layers, two free
Free US shipping · 30-day refund
Notes.
A.Is this shapewear?
No. BSLYR is a structural base layer. It's not designed to compress your body smaller — it's designed to give your outer shirt a flat, even surface to drape over. Most men buy it because their work polos and dress shirts cling and pull; the layer underneath fixes the drape.
B.How does it fit?
Compression fit runs ~1 size slim of standard US sizing. Size by your height and weight using the chart, not by your usual t-shirt size. Between two sizes, size up. Sizes S–5XL.
C.Will it ride up?
The cut runs longer than a t-shirt and the four-way stretch knit holds tension evenly through the torso. Sized correctly (by height + weight, not t-shirt size), it stays put through a full day. If it doesn't, the 30-day refund covers you.
D.What's it made of?
90% polyester, 10% spandex. Four-way stretch. Knitted-in armature pattern — not a print. Standard composition for athletic-tier compression apparel. What makes BSLYR work is how it's cut and constructed, not the fiber.
E.When will it arrive?
Built and shipped from our manufacturing partner in 5–11 business days. Tracking activates within 48–72 hours of order. Reply to your order confirmation any time for a status update.
F.What if it doesn't fit right?
30-day refund. Email hello@bslyr.com from the address you ordered with. We respond within 24 hours — real human, not a void.