AVS w/Grip Sole
The Attiva Vento and Modo models offer the calf adapter design. This is found in the upper collar of the liners. It consists of softer material in a V cut shape on the upper sides allowing the liner collar to give and adapt to various lower leg shapes.
 
AVS w/Grip Sole
New 3D construction in the collar of the Attiva Vento and Modo liners, further enhances the fit capabilities of hard to fit calves. The collar is molded 3 dimensionally in a flared positon to increase room for the calf.