Element M155 ST Spring

Irregular-pitch tuning spring for the drivetrain

The Element M155 ST Spring replaces the stock spring inside an Airsoft AEG drivetrain with a tuning spring made from hardened spring-steel wire with an irregular pitch. The M155 designation marks the spring's relative strength within the Element line-up and is meant for comparison between the steps of the series, not as a fixed muzzle-velocity figure, which depends on the piston, cylinder head and compression of the individual setup.

Effect of the winding and fitment

The uneven winding lets the spring sit more evenly inside the piston tube, cutting down on vibration and edge wear compared with a linearly wound spring. It fits standard metal gearboxes used in Airsoft AEGs and is a 1:1 replacement for the original spring.