CowCow 150% Hammer Spring for TM M&P9 Series

If you want more recoil and higher muzzle energy from your Tokyo Marui M&P9 GBB, the CowCow 150% Hammer Spring for TM M&P9 Series is what you need. This replacement hammer spring is rated at 150% of the strength of the original spring, meaning your hammer will hit the knocker valve harder and release more gas, translating into harder felt recoil and higher FPS. Naturally, this will shorten the lifespan of your M&P so proceed with caution if this is your first time upgrading a GBB pistol.