Note: All measurements are in inches unless otherwise noted

O'Brien Adults' Life Vest Sizing

VEST
XS
S
M
L
XL
XXL
3XL
4XL
5XL
Chest
28-32
32-36
36-40
40-44
44-48
48-52
52-56
56-62
62-68

O'Brien Kids' Life Vest Nylon Sizing

VEST
WEIGHT
Infant
up to 30 lbs
Child
30-50 lbs
Youth
50-90 lbs