Action Army Spring for TM VSR-10 PK248 if you already own a

if you already own a Umarex (Elite Force) H&K MP5 and have a lot of accessories lying around

Railed upper receiver perfect for optics

the system stops working and emits an elongated 'beep' sound

available in either cutoff (MS120c) or standard (MS120) 3-packs

Action Army Spring for TM VSR-10 PK248 if you already own aFeatures Steel construction for durability and consistency Tokyo Marui VSR 10 compatible Construction: Steel Compatibility: Tokyo Marui VSR 10 and other compatible Airsoft sniper rifles Manufacturer: Action Army Company Specifications: Spring Power Chart. (% FPS) FPS estimate based on average power output. Exact FPS result may vary based on alignment, installation, inner barrel, cylinder and other factors. 110% (M85) ~270~310 F. P. S. 120% (M90)