Prometheus Spring Combo Set (Includes MS100/ MS110/ MS120/ MS135)

Prometheus Spring Combo Set (Includes MS100/ MS110/ MS120/ MS135) Metal Construction MS100/ MS110/ MS120/ MS135 Power Up Non-linear, irregular pitched designed to ease wear and tear on your gearbox Heat-treated for greater strength and consistent compression Anodized paint for reduced wear and tear, minimal flaking Suitable For AEG Rifle Airsoft Guns MS spring rates are based on the rough meters per second on a 0.2g BB. You can expect roughly 100 M/S (328 FPS) +/- 5M/S on a MS100 spring. the M/S or FPS can vary considerably due to the entire build setup, so please keep this in mind when choosing a springs.