Experience the raw feedback of a true mechanical trigger combined with sniper-grade HPA consistency in the PolarStar Kythera Mechanical HPA Engine. Built for DMR marksmen, stealth recon players, and mil-sim purists, the Kythera delivers pure electro-less HPA performance. You get all of this performance with zero batteries, zero FCUs, and zero wiring to operate.
Unlike conventional electro-pneumatic HPA engines, the Kythera utilizes a patented internal mechanical valve system that resets instantly after every trigger pull. This design replicates the crisp break, tactile reset, and pull weight of a real firearm single-action trigger, giving you unmatched shot-to-shot velocity consistency, instant trigger response, and whisper-quiet performance in any weather condition.
Drops straight into standard Version 2 AEG gearbox shells with the included V2 trigger linkage and standard nozzle length.
Tailored for Version 3 gearbox shells, featuring specialized V3 trigger linkages and nozzle offsets for AK and short-line platforms.
Includes the extended nozzle and mounting hardware required for long-cylinder SR-25/V2.5 gearbox shells, making it the ultimate drop-in heart for 7.62-style DMR builds.
| Features | Details |
| Pure Mechanical Operation: | Requires no batteries, control boards, or electronic wiring, completely waterproof and unaffected by cold weather, rain, or mud. |
| Authentic Firearm Trigger Feel: | Features a true mechanical trigger mechanism with adjustable pre-travel, over-travel, and pull weight for a tactile, rifle-like break and reset. |
| Closed-Bolt Performance: | Cycles from a closed-bolt position by default, ensuring maximum accuracy, hop-up consistency, and zero nozzle wobble when firing. |
| Constant Velocity Output: | Delivers exceptional shot-to-shot consistency (typically ±2–3 FPS variance), making it the ultimate drop-in heart for DMR and sniper builds. |
| Wide Pressure & Velocity Range: | Operates cleanly across a 60–180 PSI spectrum, allowing effortless FPS tuning for standard rifleman or high-velocity DMR field limits. |
| Simple Drop-In Installation: | Designed to fit directly into standard gearbox shells with minimal modification required. |
| Specification | Details |
| Model Engine | Kythera Mechanical HPA Engine |
| Available Variants | Version 2 (M4)/Version 3 (AK)/V2 Extended (SR-25) |
| Operating System | 100% Mechanical Electro-Less Valve System |
| Operating Pressure | 60 – 180 PSI |
| Velocity/FPS Range | 270 – 500+ FPS (Adjustable via PSI & Nozzles) |
| Firing Modes | Semi-Auto Only (Mechanical Safety Included) |
| Power Source | High Pressure Air (HPA Tank & Regulator) - No Battery Required |
| Brand | Polarstar |
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