INTERNAL UPGRADE

Compatible with all Marui compatible M4 series Airsoft AEG. The Ultimate Hopup Unit designed by Madbull

Parts and Materials:
Metal body, includes a famous MadBull blue bucking (60 degree)
Tracer unit is optional.

Learn More

Charging Handle Spring Learn More

Shim set Learn More

After 6 months of trial and error, our product's performance has also been continuously improving. The color of our spring is not painted; it is hard-coated through a special process. Each spring is meticulously calculated using computer algorithms and rigorously tested with over 100,000 punches to ensure consistency in length and force. We want to demonstrate that our spring is not just any ordinary spring; it is a MadBull spring, known for its vibrant and distinct character.

Learn More

This piston is comprised of new materials never before used combined with innovative processes. The Madbull PX piston is designed with full metal teething and hardened nylon fiber. The metal teeth is produced with MIM (Metal Injection Molding), which gives the teeth a degree of flexibility without breaking. The body is molded with Blaze Orange Nylon Fiber. Learn More