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C-IN2 New York Throwback Jock in Bicycle Blue, front view of men's underwear
C-IN2 New York Throwback Jock in Bicycle Blue, men's athletic jockstrap front view
C-IN2 New York Throwback Jock in Bicycle Blue front view
C-IN2 New York Throwback Jock in Bicycle Blue, front view of men's underwear
C-IN2 New York Throwback Jock in Bicycle Blue, men's athletic jockstrap front view
C-IN2 New York Throwback Jock in Bicycle Blue front view

Product Details

Men's Cotton Jockstrap — Low-Rise Fit, Open-Back Support

The C-IN2 Throwback Jock is crafted from soft single knit jersey that delivers lightweight comfort with a vintage-inspired feel. Designed with a low-rise silhouette, it offers a sculpted, supportive fit that feels secure, breathable, and built for movement.

Contrast ribbed binding and a wide logo waistband bring throwback attitude, while elastic leg straps provide lift and definition with a confident, athletic edge. Classic, bold, and unapologetically expressive, it’s performance styling with retro roots.

Fit & Silhouette
Men's low-rise cotton jockstrap — front coverage only, with an open back and elastic leg straps running to the waistband.

Leg Straps
Wide elastic straps sit under the seat and lift, holding the shape without cutting in through a full day.

Soft Single Knit Jersey
95% Cotton, 5% Elastane. Lightweight single knit that feels broken-in from the first wear, with just enough stretch to move when you do.

Contour Pouch
1-ply contour construction shapes and lifts with a single layer of jersey. Natural definition — no padding, no bulk, nothing to adjust.

Rise
Low-rise, sitting below the natural waist so the band is the first thing that shows when your jeans sit low.

Binding & Trim
White ribbed binding outlines the pouch and straps in contrast, tracing every edge of the cut.

Waistband
2.25" elastic waistband with the C-IN2 logo repeated across it — wide, bold, and impossible to miss above a low waistband.

Fit note
True to size. Size up for a looser fit.

Care
Machine wash.
Imported.

Throwback

Throwback pulls from the past and refines it for right now — vintage silhouettes and classic athletic details rebuilt on a modern fit. Old-school influence, new-school confidence.

New

Throwback Jock Bicycle Blue

by C-IN2 New York
$28
No reviews yet
Our philanthropic promise $1.96
Where the money goes
Set aside the moment this sells, for our philanthropic programs. Allocated publicly at each milestone and reported on the tracker. Fixed when the price was set; it doesn't change after you buy. How it works
New with tags · Authentic
New with tags, from one reputable luxury supplier or direct from the brand. Never marketplaces, never individuals, never secondhand.
A real person answers
Fit, fabric, sizing: a reply within 24 hours, from a person. If something's wrong, we fix it first and explain after. Ask us
Returns
30 days from delivery, unworn, return shipping on us. Final-sale pieces are marked and can't be returned. Holiday orders can be returned through January 15.
Size Guides

Size Guide

Pick a category, find your usual size in the first column, then read across for the same size in other countries. Each table starts with body measurements so you can size from a tape measure. Where a product uses the brand's own scale, the label on that product page takes priority.

How to measure

Use a soft tape over light clothing. Keep it level and snug, not tight. Between sizes? Take the larger for outerwear, the smaller for close-fitting knits and swim.

Measurement How to take it
Chest / Bust Around the fullest part of the chest, tape under the arms and across the shoulder blades
Waist Around the natural waist, the narrowest point above the hip bones
Hips Around the fullest part of the hips and seat, feet together
Inseam From the top of the inner thigh to the ankle bone, standing straight
Foot length Stand on paper, heel to a wall, mark the longest toe; measure heel to mark. Use the longer foot
Head Around the head where a hat sits, about 1 cm (½ in) above the ears and eyebrows
Hand Around the palm at the knuckles, excluding the thumb, dominant hand
Finger Wrap paper around the finger, mark the overlap, measure in mm; or the inside diameter of a ring that fits

Measure feet and fingers at the end of the day, when they are largest.

Women's clothing

Tops, dresses, knitwear and outerwear. Size by bust.

Swipe sideways to see every column →

Size Bust in Bust cm Waist in Waist cm Hips in Hips cm US UK/AU EU/FR IT DE JP
XXS 31.5 80 24 61 34 86 0 4 32 36 30 5
XS 32.5 83 25 64 35 89 2 6 34 38 32 7
S 33.5 85 26 66 36 91 4 8 36 40 34 9
S 34.5 88 27 69 37 94 6 10 38 42 36 11
M 35.5 90 28 71 38 97 8 12 40 44 38 13
M 36.5 93 29 74 39 99 10 14 42 46 40 15
L 38 97 30.5 77 40.5 103 12 16 44 48 42 17
L 39.5 100 32 81 42 107 14 18 46 50 44 19
XL 41 104 33.5 85 43.5 110 16 20 48 52 46 21
XXL 43 109 35.5 90 45.5 116 18 22 50 54 48 23

Italian sizes run two numbers above French: a French 38 is an Italian 42. Japanese sizes run small; when in doubt go up one.

Women's bottoms, underwear & swim

Pants, shorts & skirts

Swipe sideways to see every column →

Size Waist in Waist cm Hips in Hips cm US UK/AU EU/FR IT Jeans
XXS 24 61 34 86 0 4 32 36 24
XS 25 64 35 89 2 6 34 38 25
S 26 66 36 91 4 8 36 40 26
S 27 69 37 94 6 10 38 42 27
M 28 71 38 97 8 12 40 44 28
M 29 74 39 99 10 14 42 46 29
L 30.5 77 40.5 103 12 16 44 48 30
L 32 81 42 107 14 18 46 50 32
XL 33.5 85 43.5 110 16 20 48 52 33
XXL 35.5 90 45.5 116 18 22 50 54 35

Underwear, bikinis & one-pieces

Swipe sideways to see every column →

Size Hips in Hips cm US dress UK/AU EU/FR IT Panty (US)
XS 34–35 86–89 0–2 4–6 32–34 36–38 5
S 36–37 91–94 4–6 8–10 36–38 40–42 6
M 38–39 97–99 8–10 12–14 40–42 44–46 7
L 40.5–42 103–107 12–14 16–18 44–46 48–50 8
XL 43.5–45.5 110–116 16–18 20–22 48–50 52–54 9

Bikini tops with cup sizes use bra sizing: band is underbust in inches rounded to the nearest even number; cup is bust minus band (1 in = A, 2 = B, 3 = C, 4 = D).

Men's clothing

T-shirts, shirts, knitwear, hoodies and jackets. Size by chest.

Swipe sideways to see every column →

Size Chest in Chest cm Waist in Waist cm Neck in Neck cm US/UK/AU EU/IT/FR DE JP
XS 34–36 86–91 28–30 71–76 14–14.5 36–37 XS 44 44 S
S 36–38 91–97 30–32 76–81 15–15.5 38–39 S 46 46 M
M 38–40 97–102 32–34 81–86 15.5–16 39–41 M 48 48 L
L 40–42 102–107 34–36 86–91 16.5–17 42–43 L 50 50 LL
XL 42–44 107–112 36–38 91–97 17.5–18 44–46 XL 52 52 3L
XXL 44–46 112–117 38–40 97–102 18.5–19 47–48 XXL 54 54 4L
3XL 46–48 117–122 40–42 102–107 19–19.5 48–50 3XL 56 56 5L

Italian designer pieces are often labelled by EU number only (46, 48, 50). Japanese letter sizes run one size smaller than US.

Men's bottoms, underwear & swim

Pants, shorts & joggers

Swipe sideways to see every column →

Size Waist in Waist cm Hips in Hips cm US/UK/AU EU/IT/FR DE JP
XS 28 71 34–35 86–89 28 44 44 73
S 30 76 36–37 91–94 30 46 46 76
M 32 81 38–39 97–99 32 48 48 82
M 33 84 39–40 99–102 33 49 49 85
L 34 86 40–41 102–104 34 50 50 88
L 36 91 42–43 107–109 36 52 52 91
XL 38 97 44–45 112–114 38 54 54 97
XXL 40 102 46–47 117–119 40 56 56 102
3XL 42 107 48–49 122–124 42 58 58 107

Inseam: short 30 in (76 cm), regular 32 in (81 cm), long 34 in (86 cm).

Underwear, swim briefs, trunks & swim shorts

Swipe sideways to see every column →

Size Waist in Waist cm US/UK EU IT FR JP
XS 26–28 66–71 XS 3 2 1 S
S 28–30 71–76 S 4 3 2 M
M 30–33 76–84 M 5 4 3 L
L 33–36 84–91 L 6 5 4 LL
XL 36–39 91–99 XL 7 6 5 3L
XXL 39–42 99–107 XXL 8 7 6 4L

Briefs, thongs, jocks and swim tangas are cut to fit snugly; stay with your measured size.

Women's shoes

Size by foot length; the chart allows about 1 cm (⅜ in) beyond the toe.

Swipe sideways to see every column →

Foot in Foot cm US UK EU IT JP cm AU
8.5 21.6 5 3 35.5 35 22 5
8.7 22.0 5.5 3.5 36 35.5 22.5 5.5
8.9 22.5 6 4 36.5 36 23 6
9.0 22.9 6.5 4.5 37 36.5 23.5 6.5
9.25 23.5 7 5 37.5 37 24 7
9.4 23.9 7.5 5.5 38 37.5 24.5 7.5
9.6 24.4 8 6 38.5 38 25 8
9.75 24.8 8.5 6.5 39 38.5 25.5 8.5
9.9 25.2 9 7 39.5 39 26 9
10.1 25.7 9.5 7.5 40 39.5 26.5 9.5
10.25 26.0 10 8 40.5 40 27 10
10.4 26.4 10.5 8.5 41 40.5 27.5 10.5
10.6 26.9 11 9 41.5 41 28 11
10.75 27.3 11.5 9.5 42 41.5 28.5 11.5
10.9 27.8 12 10 42.5 42 29 12

Italian-made shoes often run a half size small against the EU standard; use the IT column for Italian brands. Width: standard B / medium, wide D / W.

Men's shoes

Size by foot length; the chart allows about 1 cm (⅜ in) beyond the toe.

Swipe sideways to see every column →

Foot in Foot cm US UK EU IT JP cm AU
9.25 23.5 6 5 39 38.5 24 5
9.4 23.9 6.5 5.5 39.5 39 24.5 5.5
9.6 24.4 7 6 40 39.5 25 6
9.75 24.8 7.5 6.5 40.5 40 25.5 6.5
9.9 25.2 8 7 41 40.5 26 7
10.1 25.7 8.5 7.5 42 41 26.5 7.5
10.25 26.0 9 8 42.5 41.5 27 8
10.4 26.4 9.5 8.5 43 42 27.5 8.5
10.6 26.9 10 9 43.5 42.5 28 9
10.75 27.3 10.5 9.5 44 43 28.5 9.5
10.9 27.8 11 10 44.5 43.5 29 10
11.1 28.2 11.5 10.5 45 44 29.5 10.5
11.25 28.6 12 11 46 44.5 30 11
11.4 29.0 12.5 11.5 46.5 45 30.5 11.5
11.6 29.4 13 12 47 45.5 31 12
11.9 30.2 14 13 48.5 46.5 32 13

UK and Australian men's sizes are one number below US. Width: standard D / medium, wide EE / W.

Accessories

Hats & headwear

Swipe sideways to see every column →

Size Head in Head cm Fitted (US) UK
XS 20.5–21 52–53 6½ – 6⅝ 6⅜ – 6½
S 21.25–21.75 54–55 6¾ – 6⅞ 6⅝ – 6¾
M 22–22.5 56–57 7 – 7⅛ 6⅞ – 7
L 22.75–23.25 58–59 7¼ – 7⅜ 7⅛ – 7¼
XL 23.5–24 60–61 7½ – 7⅝ 7⅜ – 7½
XXL 24.5–25 62–63 7¾ – 7⅞ 7⅝ – 7¾

Snapbacks and adjustable caps fit S through L in one size.

Belts

Choose a belt two inches (5 cm) above your pant waist so it buckles on the middle hole.

Swipe sideways to see every column →

Pant waist in Belt in Belt cm Size
28 30 75 XS
30 32 80 S
32 34 85 S / M
34 36 90 M
36 38 95 L
38 40 100 L / XL
40 42 105 XL
42 44 110 XXL

Gloves & mittens

Swipe sideways to see every column →

Size Hand in Hand cm Men's Women's
XS 6–6.5 15–16.5 – 6
S 6.5–7 16.5–18 7 6.5
M 7–7.5 18–19 7.5 7
M / L 7.5–8 19–20.5 8 7.5
L 8–8.5 20.5–21.5 8.5 8
XL 8.5–9 21.5–23 9 –
XXL 9–9.5 23–24 9.5 –

Socks

Swipe sideways to see every column →

Size Men's US shoe Women's US shoe EU shoe
S 3–6 4–7 35–38
M 6–9 7–10 39–42
L 9–12 10–13 43–46
XL 12–15 – 47–50

Rings

Measure the inside diameter of a ring that fits, or your finger's circumference in mm. Knuckle size matters more than the base of the finger.

Swipe sideways to see every column →

Diameter mm Circ. mm US/CA UK/AU EU/ISO FR / IT JP
14.9 46.8 4 H 47 7 7
15.3 48.0 4.5 I 48 8 8
15.7 49.3 5 J½ 49 9 9
16.1 50.6 5.5 K½ 51 10.5 10
16.5 51.9 6 L½ 52 12 11
16.9 53.1 6.5 M½ 53 13 12
17.3 54.4 7 N½ 54 14.5 14
17.7 55.7 7.5 O½ 56 15.5 15
18.1 57.0 8 P½ 57 17 16
18.5 58.3 8.5 Q½ 58 18 17
18.9 59.5 9 R½ 59 19.5 18
19.4 60.8 9.5 S½ 61 21 19
19.8 62.1 10 T½ 62 22 20
20.2 63.4 10.5 U½ 63 23.5 22
20.6 64.6 11 V½ 65 24.5 23
21.0 65.9 11.5 W½ 66 26 24
21.4 67.2 12 X½ 67 27 25
21.8 68.5 12.5 Z 68 28.5 26
22.2 69.7 13 Z½ 70 29.5 27

Bags, wallets, scarves, sunglasses and other jewelry are one size; dimensions are on each product page.

Quick rules & fit notes
From To Rule
US women's dress UK / AU Add 4
US women's dress EU / FR Add 32
US women's dress IT Add 36
FR IT Add 4
US men's chest (in) EU / IT Add 10
US men's waist (in) EU / IT Add 16
US men's shoe UK Subtract 1
US women's shoe UK Subtract 2
US men's shoe EU Add 33
US women's shoe EU Add 31
Any shoe JP Foot length in cm
Pant waist (in) Belt (in) Add 2

Fit by product type

Product Fit If between sizes
Outerwear, hoodies, sweatshirts Relaxed, room for a layer Size up
T-shirts, tanks, polos True to size Stay
Performance & activewear Close to the body Size down
Underwear, briefs, swim Snug Stay
Dresses, skirts True to size Size by the larger of bust or hips
Jeans True to size; stretch relaxes with wear Size down for stretch denim
Shoes True to size Up for a thick sock, down for a narrow foot

Unisex and lifestyle pieces are cut to men's sizing; women typically take one size down.

 
Shipping calculated at checkout.

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Product Details

Men's Cotton Jockstrap — Low-Rise Fit, Open-Back Support

The C-IN2 Throwback Jock is crafted from soft single knit jersey that delivers lightweight comfort with a vintage-inspired feel. Designed with a low-rise silhouette, it offers a sculpted, supportive fit that feels secure, breathable, and built for movement.

Contrast ribbed binding and a wide logo waistband bring throwback attitude, while elastic leg straps provide lift and definition with a confident, athletic edge. Classic, bold, and unapologetically expressive, it’s performance styling with retro roots.

Fit & Silhouette
Men's low-rise cotton jockstrap — front coverage only, with an open back and elastic leg straps running to the waistband.

Leg Straps
Wide elastic straps sit under the seat and lift, holding the shape without cutting in through a full day.

Soft Single Knit Jersey
95% Cotton, 5% Elastane. Lightweight single knit that feels broken-in from the first wear, with just enough stretch to move when you do.

Contour Pouch
1-ply contour construction shapes and lifts with a single layer of jersey. Natural definition — no padding, no bulk, nothing to adjust.

Rise
Low-rise, sitting below the natural waist so the band is the first thing that shows when your jeans sit low.

Binding & Trim
White ribbed binding outlines the pouch and straps in contrast, tracing every edge of the cut.

Waistband
2.25" elastic waistband with the C-IN2 logo repeated across it — wide, bold, and impossible to miss above a low waistband.

Fit note
True to size. Size up for a looser fit.

Care
Machine wash.
Imported.

Throwback

Throwback pulls from the past and refines it for right now — vintage silhouettes and classic athletic details rebuilt on a modern fit. Old-school influence, new-school confidence.

Dark Yarn is an independent retailer. C-IN2 New York is not affiliated with Dark Yarn or its philanthropic programs.

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