Madbull M140 Upgrade Up Spring
- Consistent >100000 shotsl
- Non-liner design (calculated)
- Color coating to reduce effects from environment
- Design & Made by experienced engineers.
- Premium quality German piano wire
- Model: MB SP140
- Manufactured by: Madbull Airsoft
**We recommend upgrading to metal bushing, spring guide with bearing, reinforced gearbox, reinforced steel gear, polycarbonate piston, reinforced piston head, and battery upgrade with this spring.