Evike.com Irregular Pitch Airsoft AEG Tune-up Spring M100

Features: Irregular pitch spring coils: Variable tension. Reduces stress, wear and tear for your gearbox Strength: Made out of stainless steel. Increased tension and durability. Tension lasts 50% longer than other leading brands Compatibility: Designed for all versions of Airsoft AEG gearboxes 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. 120% (M90) ~280~340 F.P.S. 130% (M95) ~290~370 F.P.S. 140% (M100) ~320~380 F.P.S. 150% (M110) ~330~390 F.P.S. 160% (M113) ~340~400F.P.S. 170% (M115) ~350~420 F.P.S. 190% (M120) ~360~450 F.P.S. 210% (M125) ~400~470 F.P.S. 235% (M130) ~420~500 F.P.S. 260% (M140) ~450~550 F.P.S. 300% (M150) ~480~600 F.P.S. M160 : ~530+ 20 F.P.S. M170 : ~560+ 20 F.P.S. M180 : ~595+ 20 F.P.S. M190 : ~625 + 20 F.P.S.