Guarder AEG Spring

The SP-150 rating indicates the spring's stiffness, which generally correlates to a higher muzzle velocity. In most standard AEG setups, this spring is designed to push your rifle toward the higher end of the power spectrum, typically around 450-500 FPS depending on your specific air seal and barrel length.

Yes, this spring is designed for Tokyo Marui spec gearboxes, which includes most major brands like Matrix, G&G, and Classic Army. As long as your AEG uses a standard Version 2 or Version 3 gearbox, it should be compatible.

Because an SP-150 is a high-tension spring, it puts significant stress on your gearbox shell, gears, and motor. It is highly recommended that you have a reinforced gearbox shell, high-torque gears, and a high-torque motor to handle the increased load and prevent premature failure.

Oil-tempering is a heat-treatment process that significantly improves the spring's elasticity and resistance to fatigue. This means the spring will maintain its power rating for much longer without 'settling' or losing FPS over time compared to standard, non-tempered steel springs.

The SP-150 is a powerful spring intended for advanced builds rather than entry-level upgrades. If you are new to teching, we recommend starting with a lower-rated spring to learn the mechanics of your gearbox before moving to high-tension springs that require extensive internal reinforcement.