SUPER STRETCHY - SIZE Fits for shoe size 9-11/10-13/13-15 US. COOL MAX DESIGN - Your feet will keep dry and not stuffy as our special air-out design ( bulid air-bleed hole on the feet instep). NO ODOR/BTEATHABLE - You can enjoy all the benefit of this function, such as No odor and Breathable. NO FRICTION DESIGN - Your feet will be protected tenderly to reduce foot pressure and blistering (Full cushion design for sole, Seamless toe, Remember: the skin of a diabetic is so fragile that the pressure could not exceed 5N ). COMFORTABLE TOP (NON BINDING & HOLD WELL) - Your ankle will never feel tight and the socks will never loose because ( The welt of the socks adopt the 1*1 Rab knit way with wide fabric, it keeps the skin weighted evenly over the welt top, also the "Y" heel strengthen this performence).