The Donjoy Pinch Guard is an accessory to be worn with a rigid DonJoy brace. The brace shown in the photo with the pinch guard is the Armor Fourcepoint Knee Brace, this can be found here: https://www.donjoystore.com/donjoy-armor-knee-brace-with-fourcepoint-hinge
The Armor Fourcepoint is an excellent brace to be worn for contact sports like Football. The Pinch Guard is designed to be worn with a brace like the Armor when wearing a tall boot like a Ski boot or a motocross boot. It helps prevent the calf from getting pinched between the frame of the brace and the top of the boot. It really doesn't serve a purpose for football.