BIG BITE™ VALVE Easy Bite And Sip Valve Self-Seals After Each Drink LEAK-PROOF On/Off Lever.Water When You Want It, None When You Don't LARGE MOUTH OPENING Allows You To Fill The Flask Easily With Ice And Makes It Easier To Clean HYDROGUARD™ Antimicrobial Technology Inhibits The Growth Of Bacteria In The Flask BPA/BPS/BFA FREE EASY DRY HANGER LOOP Hang Flask Upside Down From Loop For Easy Drainage And Drying PACKABLE Empty Flask Collapses And Folds Ultra-Compact To Fit In Most Pockets DISHWASHER SAFE Hand Wash Vessel, Cap Is Top Rack