Well ECHO1 Well Full Metal Upgrade or Repair Spring and Piston Kit for ASR JP-54 SR-2 and MB06 Series of Bolt Action Airsoft Sniper Rifles
PLEASE NOTE: Might come with a black o-ring instead of the pictured white one.
Metal spring guide with ball bearings.
Reinforced metal piston with piston head and o-ring.
Upgraded FPS spring.