Pneumatic cushion seals function is to act as a check valve, so a separate valve is not necessary. A lip seal has a chamfer on the inside which ensures an effective cushioning process. When the direction changes, the check valve ensures the pressure can be applied on the piston surface. The pneumatic cushion seals are designed specifically for cushioning in pneumatic cylinders made of polyurethane which as a very high abrasion resistance. Abbey Seals supply a large range of high quality pneumatic cushion seals.