Laylax First Factory Gas Route Seal Gasket for Tokyo Marui M4A1 MWS GBB Magazines

Description

The LAYLAX First Factory gas route seal gasket is a replacement internal part for Tokyo Marui M4A1 MWS gas blowback magazines. It sits at the magazine’s gas outlet, the face that meets the moving nozzle in the bolt carrier group when the rifle cycles.

That junction is one of the most important sealing points in a gas blowback system. Factory rubber parts can harden, flatten or wear with repeated use, which lets propellant escape sideways instead of travelling into the action. The First Factory gasket is made from a rubber compound chosen for flexibility and low friction, with a shaped lip pattern on its upper face that presses against the underside of the nozzle to close the joint.

With the joint closed, gas is directed into the rifle’s internal cylinder block without loss of pressure. Owners fitting this part are aiming for consistent cycling, steady velocity and stronger felt recoil, including in colder conditions.