Our ultralight boot gaiters provide the needed comfort and durability for all your hiking and trail running outings. They’ll not only keep the keep dirt and debris out of your shoes, but the breathable material and unique design will make you forgot you’re even wearing the gaiters. Sizing: Place a tape measure 2” above your ankle and measure the circumference (around your leg). The small/medium boot gaiters are for 9” circumference or less. The large/x-large boot gaiters are for 9”+ circumference.