From Polarstar Airsoft we have the Kythera Semi-Auto(SA) Mechanical HPA Engine for Version 2.5 Gearboxes.
This HPA system is a radical departure from all previous systems that PolarStar has produced since the Kythera does not use a battery, an FCU or any type of electronics. The Kythera is completely mechanical. This means you never have to worry about charging batteries or work with delicate electronics. It also means that the system is completely waterproof.
Containing very few parts, it is easy to install and maintain. The Kythera incorporates a very intelligent design and is unlike anything else on the market. The system was designed as a mechanical system from the ground up and uses a realistic trigger mechanism which can be applied to single-shot, semi-automatic and fully-automatic systems.
User Manual: https://cdn.shopify.com/s/files/1/0023/7466/4301/files/Kythera_Instructions-09162020.pdf?v=1600278089
Features:
Realistic Trigger - What sets this system apart from other mechanical systems is the design of its trigger. The trigger mechanism is designed to replicate the function, weight and feel of a real single-action firearm trigger. It feels real because it is real. The hardened alloy steel sears catch and release the stainless steel spool valve in the same way the sears of a real firearm catch and release the hammer or striker. This gives the Kythera trigger the distinct break and reset you would expect to feel when firing a real single action firearm. The trigger mechanism in the Kythera SA is also adjustable, allowing the user to fine tune the weight and over travel. Additionally, the internal firing valve is balanced and the only force applied during firing is the main spring. This means the function and feel of the trigger is independent of input pressure and velocity.
Complete Shot Cycle - The design of the Kythera SA completes a shot cycle on the trigger pull. This gives you the proven closed bolt performance of the Fusion Engine and F2 in a completely mechanical, waterproof system with a realistic trigger. It does not require the trigger to be released before the nozzle chambers the next round and the firing volume is refilled. This occurs automatically and consistently every shot, with adjustable nozzle dwell and return speed. As the system resets and recharges immediately after firing, it is ready to fire again before the trigger has been released. This means the system can cycle very quickly for faster follow up shots and a lower potential for double feeding.
Extremely Efficient and Consistent - The valve design of the Kythera operates without the need for air to control the opening or closing of the valve. Without a pilot valve, 100% of the air going into the system is fired through the nozzle allowing it to operate very efficiently. In addition to being extremely efficient, the system is also extremely consistent. The valve is released at the same point every shot with the same force applied, regardless of trigger input.
Universal Charging Cord - The steel cord visible at the back of the system is attached to a cocking mechanism for the internal spool valve. Although the system automatically cocks the spool valve when the system is pressurized, since the Kythera uses a balanced valve, it is possible in certain situations that the valve could stall and needs to be manually cocked. This typically only happens if the system is run completely out of air so that the pressure drops below the operating range of the system. The cord is designed to be either routed through the grip of the rifle for easy access or even possibly attached in some fashion to the charging handle.
Easy Installation - The Kythera SA system installs into a standard gearbox as a single assembly and typically does not require any modification to the gearbox. There are no separate parts to install and the only parts needing to be retained from the gearbox is the trigger, spring guide, selector and safety components.
Wide Velocity Adjustment Range - The Kythera has a wide operating pressure range of 60psi to 180psi which allows you to fine tune the velocity of the system and tailor for different requirements and applications. Within this pressure range we observed a muzzle velocity of 270 - 500fps w/ .20g using a 6.05x380mm barrel. This lets a single Kythera be used in any role ranging from CQB to Sniper by mainly just adjusting the input pressure from your air rig.
