Systema Complete Mecha-Box for MP5 Series (A4, A5, SD5, SD6)
- Complete Drop In Gear Box for Full Stock Rear Battery MP5 with M150 Upgrade Spring for 470 - 500 FPS
- All internal parts completed upgraded with Systema Parts (gears, bearings, tappet late, cylinder, bearing spring guide rod, selector plate, low resistance wires)
- Completely Reinforced Heavy Duty Alloy Gear Box
- Includes All Helical Super Torque Up Gear Set with Bore Up Cylinder Set
- Highest Option Possible! Most Powerful! |
Customer Testimonials 
