The ProFlex 450 Comfort Hinged Soft Cap Gel Knee pads take our best-selling 350 gel knee pads and adds Comfort Hinge technology. The Comfort Hinge sets the bar for comfort in knee pads for work. The top strap sits higher on the leg and away from the back of the knee, which helps keep you from walking out of the front of the knee pad, while adding another layer of protection against impacts to the thigh. Tested and trusted by some of the most demanding knee pad users we can find: airline baggage handlers.Note: This is a non-returnable item.