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O'Neill Psycho Tech 4/3+ BZ Wetsuit-Blk/Blk View full product details

O'Neill Psycho Tech 4/3+ BZ Wetsuit-Blk/Blk

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191015072493

$499.95

$499.95 $499.95

O'Neill Size Guide

Select a category to view sizing information.

Alpha	Numeric	Chest	Waist	Hips
SM	28	36–37"	30"	36"
SM	29	36–37"	31"	37"
SM	30	36–37"	32"	38"
MD	31	38–39"	33"	39"
MD	32	38–39"	34"	40"
LG	34	41–43"	36"	42"
LG	36	41–43"	38"	44"
XL	38	45–47"	40"	46"
XL	40	45–47"	42"	48"
XXL	42	49–51"	44"	50"
XXL	44	49–51"	46"	52"
XXXL	—	53–55"	48–50"	54–56"

Size	Waist	Hip
28	28"	36"
29	29"	37"
30	30"	38"
31	31"	39"
32	32"	40"
33	33"	41"
34	34"	42"
36	36"	44"
38	38"	46"
40	40"	48"
42	42"	50"
44	44"	52"

Size	Height	Weight (lbs)	Chest	Waist
XS	5'7"–5'9"	125–140	36.5–37.5"	28.5–29.5"
S	5'8"–5'10"	135–155	37.5–39"	29.5–31"
MS	5'6.5"–5'8.5"	145–165	39–41"	31–33"
M	5'9"–5'11"	155–170	39–41"	31–33"
MT	6'1"–6'3"	160–180	39–41"	31–33"
LS	5'7.5"–5'9.5"	160–180	41–43"	33–35"
L	5'11"–6'1"	170–190	41–43"	33–35"
LT	6'2"–6'4"	180–200	41–43"	33–35"
XLS	5'8.5"–5'10.5"	180–200	43–45"	35–37"
XL	6'0"–6'2"	190–210	43–45"	35–37"
XLT	6'3"–6'5"	200–220	43–45"	35–37"
XXLS	5'9.5"–5'11.5"	200–220	45–47"	37–39"
XXL	6'1"–6'3"	210–230	45–47"	37–39"
XXXL	6'2"–6'4"	230–250	47–49"	39–44"

Metric Size Chart

Size	Height (cm)	Weight (kg)	Chest (cm)	Waist (cm)
XS	170–175	57–64	93–95	72–75
S	173–178	61–70	95–99	75–79
MS	169–174	66–75	99–104	79–84
M	175–180	70–77	99–104	79–84
MT	185–191	73–82	99–104	79–84
LS	172–177	73–82	104–109	84–89
L	180–185	77–86	104–109	84–89
LT	188–193	82–91	104–109	84–89
XLS	175–179	82–91	109–114	89–94
XL	183–188	86–95	109–114	89–94
XLT	191–196	91–100	109–114	89–94
XXLS	177–182	91–100	114–119	94–99
XXL	185–191	95–104	114–119	94–99
XXXL	188–193	104–113	119–124	99–112

Size	Bust	Waist	Hip
XS (0-1)	32–33"	24–25"	34–35"
S (3-5)	34–35"	26–27"	36–37"
M (7-9)	36–37"	28–29"	38–39"
L (11-13)	38.5–40"	30.5–32"	40.5–42"
XL (15)	41.5"	33.5"	43.5"

Size	Waist	Hip	Inseam
24	24"	35"	27"
25	25"	36"	27"
26	26"	37"	27"
27	27"	38"	27"
28	28"	39"	27"
29	29"	40"	27"
30	30"	41"	27"
31	31"	42"	27"
32	32"	43"	27"

Size	Bust	Waist	Hip	US Cup
XS	32–33"	24–25"	34–35"	A
S	34–35"	26–27"	36–37"	A–B
M	36–37"	28–29"	38–39"	B–C
L	38.5–40"	30.5–32"	40.5–42"	C–D
XL	41.5"	33.5"	43.5"	D

Size	Height	Weight (lbs)	Chest	Waist	Hip
2	5'1"–5'3"	90–105	30.5–31.5"	24–25"	34.5–35.5"
4	5'3"–5'5"	100–115	31.5–32.5"	25–26"	35.5–36.5"
6S	5'2"–5'4"	105–120	32.5–34"	26–27.5"	36.5–38"
6	5'4"–5'6"	110–125	32.5–34"	26–27.5"	36.5–38"
6T	5'6"–5'8"	115–130	32.5–34"	26–27.5"	36.5–38"
8S	5'3"–5'5"	115–130	34–35.5"	27.5–29"	38–39.5"
8	5'5"–5'7"	120–135	34–35.5"	27.5–29"	38–39.5"
8T	5'7"–5'9"	125–140	34–35.5"	27.5–29"	38–39.5"
10S	5'4"–5'6"	125–140	35.5–37"	29–30.5"	39.5–41"
10	5'6"–5'8"	130–145	35.5–37"	29–30.5"	39.5–41"
12	5'7"–5'9"	135–155	37–38.5"	30.5–32"	41–42.5"
14	5'9"–5'11"	145–165	38.5–40"	32–33.5"	42.5–44"
16	5'10"–6'0"	155–175	40–41.5"	33.5–35"	44–45.5"

Metric Size Chart

Size	Height (cm)	Weight (kg)	Chest (cm)	Waist (cm)	Hip (cm)
2	155–160	41–48	77–80	61–64	88–90
4	160–165	45–52	80–83	64–66	90–93
6S	157–162	48–54	83–86	66–70	93–97
6	163–168	50–57	83–86	66–70	93–97
6T	168–173	52–59	83–86	66–70	93–97
8S	160–165	52–59	86–90	70–74	97–100
8	165–170	54–61	86–90	70–74	97–100
8T	170–175	57–64	86–90	70–74	97–100
10S	163–168	57–64	90–94	74–77	100–104
10	168–173	59–66	90–94	74–77	100–104
12	170–175	61–70	94–98	77–81	104–108
14	175–180	66–75	98–102	81–85	108–112
16	178–183	70–79	102–106	85–89	112–116

Size	Bust	Waist	Hip
XS	32–33"	24–25"	34–35"
S	34–35"	26–27"	36–37"
M	36–37"	28–29"	38–39"
L	38.5–40"	30.5–32"	40.5–42"
XL	41.5"	33.5"	43.5"

Size	Chest	Waist
XS	34–36"	28–30"
S	36–38"	30–32"
M	38–40"	32–34"
L	40–42"	34–36"
XL	42–44"	36–38"
2XL	44–46"	38–40"

Size	Height	Weight (lbs)	Chest	Waist
4	3'10"–4'1"	35–45	23"	21"
6	4'1"–4'4"	40–55	24"	22"
8	4'4"–4'7"	50–65	26"	23"
10	4'7"–4'10"	60–75	27.5"	24"
12	4'10"–5'1"	70–85	29"	25"
14	5'1"–5'4"	80–100	30.5"	26"
16	5'4"–5'7"	90–115	32"	27"

Metric Size Chart

Size	Height (cm)	Weight (kg)	Chest (cm)	Waist (cm)
4	117–124	16–20	58	53
6	124–132	18–25	61	56
8	132–140	23–30	66	58
10	140–147	27–34	70	61
12	147–155	32–39	74	64
14	155–163	36–45	78	66
16	163–170	41–52	81	69

Size	Height	Weight (lbs)	Chest	Waist
XS (6/7)	46–49"	47–53	25"	22"
S (8)	50–53"	54–63	26.5"	23"
M (10/12)	54–57"	64–75	28"	24"
L (14/16)	58–61"	76–87	30"	25"
XL (18/20)	62–65"	88–110	32"	26"

Size	Height	Weight (lbs)	Chest	Waist	Hip
XS (6/7)	46–49"	47–53	25"	22"	26"
S (8)	50–53"	54–63	26.5"	23"	27.5"
M (10/12)	54–57"	64–75	28"	24"	29"
L (14/16)	58–61"	76–87	30"	25"	31"
XL (18/20)	62–65"	88–110	32"	26"	33"

US Men's	US Women's	EU	UK
4	5	36	3.5
5	6	37	4.5
6	7	38/39	5.5
7	8	40	6.5
8	9	41	7.5
9	10	42	8.5
10	11	43/44	9.5
11	12	45	10.5
12	13	46	11.5
13	14	47/48	12.5
14	15	49	13.5

Size	Hand Circumference
XS	6.5–7"
S	7–7.5"
M	7.5–8"
L	8–8.5"
XL	8.5–9"
2XL	9–9.5"

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The Perfect Balance of Warmth and Flexibility. Z.E.N. Zip Closure (Back Zip) 360 Barrier With Drain Holes (F.U.Z.E.) Anti-Flush Barrier (Z.E.N. Zip) Super Seal Low Profile Cuffs Stitch-less Seam Technology Wind-Proof Smoothskin Plasma Wrist and Ankle Seals Redzone Water Resistant Zipper Krypto Knee Padz Fluid Seam Weld Arms/ Shoulders/ Shins/ Calf: TechnoButter 3 Chest / Back: TechnoButter 3 Air-Firewall Smoothskin Thigh/ Butt: TechnoButter 3 Firewall PLUS (+) = 0.5mm Extra thickness for even more warmth Aqua Alpha Solvent Free Neoprene Lamination

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O’Neill is a pioneering surf brand that helped define modern surfing—innovating everything from the first wetsuit to today’s high-performance gear built for comfort, durability, and progression in the water.

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Size	Waist	Hip
28	28"	36"
29	29"	37"
30	30"	38"
31	31"	39"
32	32"	40"
33	33"	41"
34	34"	42"
36	36"	44"
38	38"	46"
40	40"	48"
42	42"	50"
44	44"	52"

Size	Waist	Hip	Inseam
24	24"	35"	27"
25	25"	36"	27"
26	26"	37"	27"
27	27"	38"	27"
28	28"	39"	27"
29	29"	40"	27"
30	30"	41"	27"
31	31"	42"	27"
32	32"	43"	27"

Size	Waist	Hip
28	28"	36"
29	29"	37"
30	30"	38"
31	31"	39"
32	32"	40"
33	33"	41"
34	34"	42"
36	36"	44"
38	38"	46"
40	40"	48"
42	42"	50"
44	44"	52"

Size	Waist	Hip	Inseam
24	24"	35"	27"
25	25"	36"	27"
26	26"	37"	27"
27	27"	38"	27"
28	28"	39"	27"
29	29"	40"	27"
30	30"	41"	27"
31	31"	42"	27"
32	32"	43"	27"

Size	Waist	Hip
28	28"	36"
29	29"	37"
30	30"	38"
31	31"	39"
32	32"	40"
33	33"	41"
34	34"	42"
36	36"	44"
38	38"	46"
40	40"	48"
42	42"	50"
44	44"	52"

Size	Waist	Hip	Inseam
24	24"	35"	27"
25	25"	36"	27"
26	26"	37"	27"
27	27"	38"	27"
28	28"	39"	27"
29	29"	40"	27"
30	30"	41"	27"
31	31"	42"	27"
32	32"	43"	27"