NBU cylinder set for AK

NBU cylinder set for increasing the performance of AK series airsoft guns.

Recommended barrel length is 400 - 550 mm.

Package contents

• Full chrome cylinder with ribbed surface for better cooling.
• Polycarbonate, silent, anti-pressure piston head with bearing.
• Aluminum cylinder head with double seal and rubber face.
• Aluminium nozzle 19,70 mm with O-ring.
• Sector gear delayer clip

What is NBU

It is an abbreviation of New Bore-Up. The parts (usually a set of piston head, cylinder head, cylinder and nozzle) have an enlarged inner diameter, so they can hold a larger volume of air and achieve higher performance. To achieve the proper effect, it is recommended to use M130 to M170 spring. The increase in performance due to NBU is about 3 - 10 m/s.