The Silverback Airsoft M90 APS 13mm Type Spring for SRS Pull Bolt Version, 13 mm outside diameter, 11 mm inside. The APS large type is suitable for APS-2, APS-T96, APS-SR2, M24 versions.

Items included:

1x Silverback Airsoft M90 APS 13mm Type Spring

This piston head feature:

– Viton Oring with a ventilated design.

– No airbrake, short, medium & long airbrake options (for 4.60 mm internal nozzle – for TAC-41 GBB cylinder head only).

– POM piston ring

– NBR 80° Oring damper

– Stainless s