Bison Motorcycle Racing TPU Knee PucksWhen you're a professional knee dragger, you need pro level pucks. By nature, these TPU filament pucks offer a high melting point and high inbuilt hardness (Shore 80A). This more durable compound allows us to shape them in a lower profile than our standard ABS pucks. The TPU compound gives a great feel during the slide, and rubber loops on the backing make for easier removal once you've finally worn them out.