Thrills Women's Undertow Surf Short in Dark Cocoa, front view showing white lace-up waist and contrast stitching

Thrills Women's Undertow Surf Short in Dark Cocoa, back view showing flap pocket and contrast stitching

Thrills Women's Undertow Surf Short in Dark Cocoa, full-length front model view styled with a white tee

Thrills Women's Undertow Surf Short in Dark Cocoa, outdoor model view on rocks beside water

Thrills

Thrills Women's Undertow Surf Short — Dark Cocoa

$80.00

Shipping calculated at checkout.

Size: 6 6 8 10 12

Product variants

Pickup available at Shop 3/1 Rainbow Beach Road

Usually ready in 2 hours

Four-way freedom for days that start in the surf and finish wherever the coast takes you.

The Thrills Undertow Surf Short in Dark Cocoa combines a fixed-waist boardshort silhouette with quick-dry stretch fabric for easy movement in and out of the water. Made from 88% nylon and 12% elastane, its four-way stretch construction lets you move freely without leaving that classic surf look behind. Pair the rich brown colourway with a bikini top for beach time or a fitted tank when you're heading into town.

Details

Fit: Fixed-waist boardshort silhouette.
Fabric: 88% nylon and 12% elastane with four-way stretch.
Performance: Quick-dry construction and stretch for freedom of movement in and out of the water.
Care: Hand or machine wash on a cold gentle cycle with like colours. Do not bleach or tumble dry. Lay flat to dry. Cool iron.
Colourway: Dark Cocoa, a rich brown base that's easy to pair with your favourite swim and casual tops.

Design Features

Fixed-waist design.
Boardshort silhouette.
Four-way stretch construction.
Quick-drying fabric.
Clean, versatile Dark Cocoa colourway.

Why You'll Love It
Quick-dry fabric and four-way stretch make this an easy choice when your day moves between the water and the shore.

Perfect For
Paddling out at your favourite break and chasing one more set before lunch, these are the surf shorts built for days when freedom of movement comes first.

Size Guide
Available in sizes 6–12.

Keep the board nearby and let the tide set the pace.

For help finding your perfect fit, call us on 07 5486 3099 — our team is happy to hand-measure any garment and walk you through sizing and fit options.

Available now at 13th Beach Surf with fast Australia Wide Shipping From our store in Rainbow Beach Queensland.

Collapsible row

Every brand fits a little differently, so tap your brand below to open its size chart. Not sure which size to pick? Call us on 07 5486 3099. Our team is happy to hand-measure any garment and walk you through sizing and fit options.

Women's Tops
Body measurements for all women's tops, dresses, playsuits, jumpsuits, jackets and jumpers.

	XS	S	M	L	XL
AU/UK	6	8	10	12	14
US	2	4	6	8	10
EU	34	36	38	40	42
Bust (cm)	79-83	84-88	89-93	94-98	99-103
Waist, at smallest point (cm)	61-65	66-70	71-75	76-80	81-85
Hips, at widest point (cm)	89-93	94-98	99-103	104-108	109-113

Women's Bottoms
Body measurements for all women's bottoms.

	XS	S	M	L	XL
Pants	24	26	28	30	32
AU/UK	6	8	10	12	14
US	2	4	6	8	10
EU	34	36	38	40	42
Waist, at smallest point (cm)	61-65	66-70	71-75	76-80	81-85
Hips, at widest point (cm)	89-93	94-98	99-103	104-108	109-113

Women's Intimates
Body measurements for all women's intimates.

	XS	S	M	L	XL
AU	6	8	10	12	14
US	2	4	6	8	10
EU	34	36	38	40	42
Bust (cm)	79-83	84-88	89-93	94-98	99-103
Underbust (cm)	68-72	73-77	78-82	83-87	88-92
Waist, at smallest point (cm)	61-65	66-70	71-75	76-80	81-85

Sizing tips
Choose your normal running shoe size when ordering Archies thongs or slides. If you're normally a half size, size up to the nearest full size (for example, if you're a 7.5, order an 8).

Women's Thongs & Slides

US Women's	UK	EU	Foot length (cm)
5	3	36-36.5	22-22.5
6	4	37-37.5	22.6-23.4
7	5	38.5-39	23.5-24.2
8	6	39.5-40	24.3-25
9	7	41-41.5	25.1-26
10	8	42.5-43	26.1-26.7
11	9	43.5-44	26.8-27.5
12	10	45-45.5	27.6-28.3
13	11	46-46.5	28.4-29.1
14	12	47.5-48	29.2-30
15	13	48.5-49	30.1-30.8
16	14	50-50.5	30.9-31.6

Men's Thongs & Slides

US Men's	UK	EU	Foot length (cm)
4	3	36-36.5	22-22.5
5	4	37-37.5	22.6-23.4
6	5	38.5-39	23.5-24.2
7	6	39.5-40	24.3-25
8	7	41-41.5	25.1-26
9	8	42.5-43	26.1-26.7
10	9	43.5-44	26.8-27.5
11	10	45-45.5	27.6-28.3
12	11	46-46.5	28.4-29.1
13	12	47.5-48	29.2-30
14	13	48.5-49	30.1-30.8
15	14	50-50.5	30.9-31.6

This is a general guide to Rhythm sizing to help you compare against your own measurements. Some styles may fit differently, and any fit notes are listed in the product description.

Women's Swim & Apparel

AU Size	6	8	10	12	14	16
US Size	2	4	6	8	10	12
International	XS	S	M	L	XL	XXL
Bust	80cm	84cm	88cm	92cm	96cm	100cm
Waist	64cm	68cm	72cm	76cm	80cm	84cm
Hips	91cm	95cm	99cm	103cm	107cm	111cm

Men's Tops

Size	XS	S	M	L	XL	XXL
Height	155-160cm	160-165cm	165-170cm	170-180cm	180-190cm	190cm
Chest	86.5cm	91cm	96.5cm	101cm	106.5cm	111.5cm

Men's T-shirts
Garment measurements by fit.

Vintage T-shirts: relaxed, boxy style. Wider through the body and neck opening, with dropped shoulders, a slightly longer sleeve and a thick 1x1 neck rib.

Size	XS	S	M	L	XL	XXL
Shoulder	44.5cm	46cm	47.5cm	49cm	50.5cm	53cm
Chest	52.5cm	54.5cm	56.5cm	58.5cm	60.5cm	63.5cm
Length	65cm	67cm	69cm	71cm	73cm	76cm

Band T-shirts: cropped length. Inspired by early-60s military sporting tees, with cropped sleeves and body for a boxy look that sits below the waist, plus a wider 1x1 neck rib.

Size	XS	S	M	L	XL	XXL
Shoulder	46.5cm	48cm	49.5cm	51cm	52.5cm	54cm
Chest	50.5cm	52.5cm	54.5cm	56.5cm	58.5cm	60.5cm
Length	60cm	62cm	64cm	66cm	68cm	70cm

Relaxed Fit T-shirts: regular length. A timeless everyday cut, not too loose and not too tight through the body and sleeves, with a regular 1x1 neck rib.

Size	XS	S	M	L	XL	XXL
Shoulder	44.5cm	46cm	47.5cm	49cm	50.5cm	53cm
Chest	52.5cm	54.5cm	56.5cm	58.5cm	60.5cm	63.5cm
Length	66cm	68cm	70cm	72cm	74cm	77cm

Men's Pants, Shorts & Trunks

Size	28	30	32	33	34	36
Waist	76.5cm	81.9cm	87cm	89.5cm	92.1cm	97.2cm

How to measure
Bust: measure under your arms at the fullest part of your bust, keeping the tape level across your shoulder blades.
Chest: measure under your arms at the fullest part of your chest, keeping the tape level across your shoulder blades.
Waist: measure around your natural waistline, with the tape sitting comfortably loose.
Hips: measure around the fullest part of your low hip, keeping the tape level across your backside.

All measurements are body measurements in centimetres.

Women's Size Guide

Size	AU	Pants	Chest	Waist	Hip
XXS	6	24	76-79	59-61	84-87
XS	8	25-26	81-84	64-66	90-92
S	10	27-28	86-89	69-71	95-97
M	12	29-30	91-94	74-76	100-102
L	14	32	96-99	79-81	105-107
XL	16	33	101-104	84-86	110-112
XXL	18	34	106-109	89-91	115-117

Men's Size Guide

Size	AU	Height	Chest	Waist	Hip
XS	28-29	168-171	85-88	70-73	85-88
S	30-31	173-176	90-93	75-78	90-93
M	32-33	178-181	95-98	80-83	95-98
L	34-35	183-186	100-103	85-88	100-103
XL	36-38	188-193	105-108	90-95	105-108
XXL	40-42	195	110-113	100-105	110-113
XXXL	44	195	115	115	115

Body measurements and international size conversions.

Women's Tops

INTL	AU/UK	US	EU	Bust (cm)	Waist (cm)
XXS	4	0	32	72-76	54-58
XS	6	2	34	77-81	59-63
S	8	4	36	82-86	64-68
M	10	6	38	87-91	69-73
L	12	8	40	92-96	74-78
XL	14	10	42	97-101	79-83
XXL	16	12	44	102-106	84-88

Women's Bottoms

INTL	AU/UK	US	EU	Waist (in)	Waist (cm)	Hip (cm)
XXS	4	0	32	22	55-57	81-83
	5			23	58-59	84-85
XS	6	2	34	24	60-62	86-88
	7			25	63-64	89-90
S	8	4	36	26	65-67	91-93
	9			27	68-69	94-95
M	10	6	38	28	70-72	96-98
	11			29	73-74	99-100
L	12	8	40	30	75-78	101-104
XL	14	10	42	32	79-83	105-109
XXL	16	12	44	34	84-88	110-114

Men's Tops

INTL	AU/UK	US	EU	Chest (cm)	Length (cm)
XXS	32	32	42	82-85	68-69
XS	34	34	44	86-89	70-71
S	36	36	46	90-93	72-73
M	38	38	48	94-97	74-75
L	40	40	50	98-101	76-77
XL	42	42	52	102-105	78-79
XXL	44	44	54	106-109	80-81

Men's Bottoms

INTL	AU/UK	US	EU	Waist (cm)	Hip (cm)
XXS	26	26	42	64-69	80-84
XS	28	28	44	69-74	85-89
	29	29		72-78	88-92
S	30	30	46	74-81	90-94
	31	31		77-82	93-97
M	32	32	48	79-83	95-99
	33	33		82-86	98-102
L	34	34	50	84-88	100-104
XL	36	36	52	89-93	105-109
XXL	38	38	54	94-98	110-114

Women's Swimwear
Body measurements in centimetres.

	XXS	XS	S	M	L	XL	XXL	XXXL
AUS/NZ	6	8	10	12	14	16	18	20
Bust	82	84.5	87	92	97	102	107	112
Waist	62	64.5	67	72	77	82	87	92
Hip	92	94.5	97	102	107	112	117	122
Underbust	69	71.5	74	79	84	89	94	99
A-cup bust	79.5	82	84.5	89.5	94.5
D-cup bust	84.5	87	89.5	94.5	99.5	104.5	109.5	114.5
DD-cup bust		89.5	92	97	102	107	112	117
E-cup bust		92	94.5	99.5	104.5	109.5	114.5	119.5
F-cup bust		94.5	97	102	107	112	117	122
G-cup bust		97	99.5	104.5	109.5	114.5	119.5	124.5

Women's Clothing

	XS	S	M	L	XL	XXL
AUS/NZ	8	10	12	14	16	18
Bust (with bra)	85cm	90cm	95cm	100cm	105cm	110cm
Bust (no bra)	83cm	88cm	93cm	98cm	103cm	108cm
Waist	65cm	70cm	75cm	80cm	85cm	90cm
Hip	95cm	100cm	105cm	110cm	115cm	120cm
Rib cage / underbust	69cm	74cm	79cm	84cm	89cm	94cm
Across shoulder	37.8cm	39cm	40.2cm	41.4cm	42.6cm	43.8cm
Across back	37.8cm	39cm	40.2cm	41.4cm	42.6cm	43.8cm

Body measurements in centimetres.

Women's Tees, Tanks, Shirts & Dresses

AU Size	Bust	Waist	Hip	US	EU
4	75	57	85	0	32
6	80	62	90	2	34
8	85	67	95	4	36
10	90	72	100	6	38
12	95	77	105	8	40
14	100	82	110	10	42
16	105	87	115	12	44
18	110	92	120	14	46

Women's Pants, Jeans, Shorts & Skirts

AU Size	Waist	Hip	Inch	US	EU
4	57	85	22	0	32
6	62	90	24	2	34
7	64.5	92.5	25	3	35
8	67	95	26	4	36
9	69.5	97.5	27	5	37
10	72	100	28	6	38
11	74.5	102.5	29	7	39
12	77	105	30	8	40
14	82	110	32	10	42
16	87	115	34	12	44
18	92	120	36	14	46

Men's Tees, Tanks & Shirts

Size	XS	S	M	L	XL	XXL
Neck	38	39	40	41	42	43
Chest	86-91	91-96	96-101	101-106	106-111	111-116
Waist	71	76	81	86	91	96
Related size	28	30	32	34	36	38

Men's Pants, Jeans & Shorts

Size	Waist	Hip	Inleg	Related size
28	71	94	82	XS
29	73.5	96.5	82.5	XS-S
30	76	99	83	S
31	78.5	101.5	83.5	S-M
32	81	104	84	M
33	83.5	106.5	84.5	M-L
34	86	109	85	L
36	91	114	86	XL
38	96	119	87	XXL

Body measurements in centimetres, taken snug over the skin.

Women's Tops & Bottoms
Bust applies to tops. Junior size applies to bottoms.

Size	Size #	Jr. size	Height	Bust	Waist	Fullest hip
XS	24	0	155-163	79-81	59.5	84-86
XS	25	1	155-163	81-84	62	86-90
S	26	3	163-170	84-86	64.5	90-92
S	27	5	163-170	86-89	67	92-94
M	28	7	163-170	89-91	70	94-96
M	29	9	165-175	91-94	72	96-99
L	30	11	165-175	94-99	75-77	99-101
XL	31	13	165-175	99-101	80	104-106
XXL	32	15	165-175	101-104	82.5	106-109
12W	12W		165-175	104-106	84-88	106-109
14W	14W		165-175	106-109	88-94	111-114
16W	16W		165-175	109-114	95-100	119-124
18W	18W		165-175	114-119	101-106	124-129
20W	20W		165-175	119-124	107-113	129-134
22W	22W		165-175	124-129	111-116	134-139
24W	24W		165-175	129-134	116-122	139-145
26W	26W		165-175	134-139	122-127	145-150

Men's Tops

Size	Height	Neck	Across shoulder	Chest	Sleeve (from centre back neck)	Bicep
XS	167-170	35.5	42	81-86	75-80	30
S	172-177	36-37	44	86-91	81-84	32
M	177-185	38-39	46	96-101	85-88	34
L	180-188	40-42	48	106-111	90-93	36
XL	183-190	43-44	50	112-117	93-95	38
XXL	183-190	45-46	52	117-122	93-95	40

Men's Pants & Shorts
Covers fixed-waist bottoms, elastic-waist shorts and pants, and shorts. Inseam applies to fixed-waist pants. XS/26 is available in shorts only, and elastic-waist styles run up to XXL/42.

Size	Height	Waist	Hips	Thigh	Inseam
XS/26	165-167	66	81-84	49
XS/27	167-170	68	84-86	50	76
S/28	167-170	71	86-88	51.5	76
S/29	172-177	74	89-91	53	76
S/30	172-177	76	91-94	54	81
M/31	177-185	79	94-96	55.5	81
M/32	177-185	81	96-98	56.5	81
M/33	177-185	84	99-101	58	81
L/34	180-188	86	102-104	59	81
L/36	180-188	92	104-107	61.5	84
XL/38	183-190	96	107-109	64	84
XL/40	183-190	102	109-112	67	84
XXL/42	183-190	106	112-115	70	84
XXXL/44	183-190	111	116-123	71.7	84
XXXL/46	183-190	117	123-127	74.3	84