Madbull Shark hop-up rubber, 60 degrees (red) is made of silicone, which prevents it from freezing in cold temperatures. Madbull Shark hop-up rubbers are designed to only allow one bullet to enter the chamber at a time, therefore this hop-up rubber reduces feed errors. Most often, Madbull Shark red is seen in HPA guns due to the double lips of the rubber, which help to stop the bullet.
