Dark Lightning kids wetsuits are designed in a "tight/snug fitting" with soft/ultra stretch neoprene to against cold. 2/2 mm : 2mm torso / 2mm arms and legs, suggest for over 65°F water. Flatlock stitching for a water resistant closure / Back zip system - easy to put on/take off for beginner. Dressing Tips: / [important] Please read the size chart first / A proper fitting wetsuit will be challenging to put on when dry. (Pro Tip: Keeping your socks on will allow your feet to slide in much easier!) / Once on, lift your arms over your head and stretch out your shoulders. This move should only be slightly restricting. / You should be able to squat down and move your arms easily / Contact us to exchange/refund, if there is any quality issue in 12 months Dark Lightning kids Shorty Wetsuit, 3mm Premium Neoprene Wet Suit to Keep Warm, One Piece Jump suit for learning to swim or in the Beach, Paddle, Diving, Surfing, Snorkeling, Fishing, kayaking, and snorkeling watersports. Â Features: >>> The neck skin design fits your skin, making the wearer fit and comfortable. >>> 3mm neoprene (SCR) +Lycra, Keeps children staying warm and added buoyancy in the water. >>> Offers 50+UV protection, Helps to shield children from UV rays. >>> Long back zipper strap, easy to put it on and take it off.