DeFeet AirEator HiTop Monkey Junky Cycling/Running Socks (Monkey Junky - L) The original air-flow design sock! Very thin sock without much cushion, excellent for use with close fit shoes Super light, low bulk, and fast drying! Aireator mesh on top of sock helps air flow and keeps your feet comfortable No-slip cuff helps keep the sock up! 39% fresh FX, 40% Nylon,1% Lycra