XPRESSCOOL Liner Recommend half sizes order up 100% Waterproof Measurements were taken from a size 9. There may be slight variations based on size. Shaft Circumference is 12.6 inches XTRATUF is proud to be the Official Boot of USRowing! This special edition Ankle Deck Boot features a new USRowing design and is still 100% waterproof, non-marking, and slip-resistant. From anglers on the open water to athletes performing on a global stage, the ADB is Built For All.