Master Mods Premium Hop Up Upgrade Parts by ASG is our newest line of premium hop up upgrade parts. Using refined air efficiency parts, the Master Mods line guarantees near perfect compression with any hop up chamber/barrel along with superior air efficiency and durability.

-Hop Up Tensioner

-AEG R-Hop Bucking

-VSR/GBB R-Hop Bucking

The Master Mods nub is made of high quality CNC brass.