GATE Eon Protector Rev 3 CNC Aluminum Cylinder Head for Airsoft AEG Gearboxes

The GATE Eon Protector Rev 3 is a cylinder head for Version 2 gearbox builds. It replaces the stock plastic piece at the front of your gearbox shell and handles the air seal between the cylinder and nozzle. That's where consistency starts: a bad seal here wastes air, makes velocity jump around, and can wear out your gearbox faster than it should.

What makes this different. GATE machined this from aluminum instead of the usual polymer, which holds its shape better under repeated piston impacts. The Rev 3 design enlarged the centering openings so it fits more cleanly in the shell, and widened the tappet plate contact area to play nice with different manufacturer parts. The nozzle guide has tighter tolerances to cut down on feeding issues. None of this is magic, but it's the kind of refinement you notice when you're already chasing consistency.

The bumpers. You get two hardness options in the box: 40° and 60° Shore A. The softer one absorbs more impact and is kinder to your gearbox shell. The harder one transfers more force, which can help with air seal at the cost of more wear on the shell and piston head. Pick based on what you're running and how much you value longevity versus raw efficiency.

What you need to know before you buy. This is not a complete upgrade kit. It's one piece of the air seal puzzle. If your nozzle is worn, your bucking is shot, or your piston head has a cracked O-ring, a new cylinder head won't fix the inconsistency. Also, installing this means opening the gearbox, so you're already in there — make sure you're shimming your gears and checking your piston too.

Compatible with all standard AEG cylinders, piston heads, and O-rings. The package includes the cylinder head, both bumper hardnesses, replacement O-rings, and a QR code linking to the quick-start guide.