Extra Fit Cylinder head AEG Mk.II uni V2/3, standard

Medium Length Nozzle – optimal for using nozzles in the range of 20–24 mm lengths (AK and AR15 type weapons and similar)

Extra Fit nozzle with an enlarged diameter of 5.40 mm (also available in a version with a standard nose diameter of 5.35 mm)

Increased lift of the nozzle arm compared to standard cylinder heads

You can use a nozzle up to 1 mm longer, thus ensuring improved sealing between the nozzle and hop-up rubber during firing

Eliminates potential feeding issues while maintaining perfect sealing between the nozzle and hop-up rubber

Unique system for securing the cylinder head in the gearbox, making it a truly universal cylinder head for gearboxes V2 and V3 of various manufacturers

Mounting holes for gearbox retention pins designed for optimal fitting into Retro Arms brand gearboxes

Impact pads made of polyurethane (PU) rubber with hardness levels of 70, 80, and 90 sh with maximum impact surface - thickness 3 mm

• 70 sh for springs up to SP130 strength
• 80 sh for springs up to SP160 strength
• 90 sh for SP170 and stronger springs

For high-rate-of-fire and high-capacity weapons (typically machine guns), where continuous shooting of long bursts of 100+BB is expected, it is recommended to use a spring with one hardness level lower than the chosen impact pad hardness (e.g., for 70 sh hardness, choose a maximum SP120 spring).

Also available without an impact pad for easy use with any PU pad or Sorbopad of the chosen hardness according to the used spring and impact pad height for AOE adjustment

Compared to the Mk.I version, the H+PTFE surface treatment has been added, the nozzle length has been extended, the nozzle diameter has been modified, and the impact pad has been redesigned for better energy distribution upon impact

Made from aerospace-grade aluminum alloy EN AW 7075-T6, with a proven H+PTFE surface treatment for ideal sliding properties while maintaining high surface abrasion resistance

Impact pad made of PU rubber and sealing O-rings made of NBR 70 sh rubber

Made in the Czech Republic

Package Contents

1× cylinder head with attached impact pad of the specified hardness and equipped with two sealing O-rings (21×1.5)

2× fixing screw M3×2

2× fixing screw M3×3

The EPeSní cylinder head brings a unique design solution:

Increased lift of the nozzle arm

The surface where the nozzle arm stops in its upper stroke is shifted compared to the standard construction. With an appropriate nozzle arm (for example, SHS) or a piston cam increasing the lift of the arm and a modified cylinder, a nozzle up to 1 mm longer than usual for the given type of weapon can be used. Owners of a gearbox V2 will particularly appreciate this innovation, as the gearbox V3 is already designed with a greater lift of the arm compared to V2.

It is not a problem, if desired, to use a 22mm nozzle in the AR15 assembly, ensuring a higher seal between the nozzle and the hop-up chamber, or the collar of the hop-up rubber. It also helps with better weapon feeding in problematic cases and thus solves the eternal dilemma: "A longer nozzle will seal better, but the weapon will no longer reliably feed BBs, or it will stop feeding altogether. A shorter nozzle will reliably feed BBs, but I will sacrifice performance." With the EPeS airsoft Mk.II cylinder head, compromises are no longer necessary, and both stable performance and reliable feeding can be achieved.

Unique gearbox head seating system

The EPeS airsoft Mk.II cylinder head has two M3 threads for set screws that screw in from the front of the cylinder head, reducing the side holes for gearbox pins. This allows the cylinder head to be seated flush against the gearbox without any play. This ensures trouble-free operation of the entire airsoft system without loss of performance or other issues leading to premature wear of parts.

Incorrectly seated wobbling cylinder head allows too much axial play of the nozzle, bringing a whole range of problems (loss of performance, inconsistent performance, nozzle jamming in the hop-up chamber, feeding problems, etc...). Last but not least, uneven contact of the piston head with the cylinder head stop, which can result in piston head destruction, and ultimately, the piston itself.

Installation is simple; by gradually tightening the screws, we reduce the hole for the gearbox pin and thus define any play in the seating. We proceed by trial and error until we achieve a firm seating of the cylinder head. This way, a truly universal solution for cylinder head seating can be achieved in the vast majority of available gearboxes. The default position of the holes is optimized for gearboxes from the Czech manufacturer Retro Arms. Warning: We strongly recommend securing the screws with high-strength threadlocker!