Polarstar

PolarStar's premium engine: highly efficient and by far the most versatile, the F2 maximises customisability to give the player exactly what they want from their dream HPA build.
From high-ROF beasts to silent and snappy DMR builds, any airsoft player could use an F2 engine to suit and advance their own playstyle.

Featuring dual solenoids, allowing for individual adjustment of the nozzle and the poppet valve.

PolarStar's Kythera engine only has a semi-automatic fire mode, owing to its entirely mechanical design. The primary benefit of a mechanical HPA engine is the silence of each shot; the Kythera is one of the quietest on the market. Perfect for DMR builds, or sneaky players who need not rely on spray-n-pray tactics.

The JACK is a simpler design than PolarStar's premium F2 - it features less parts, meaning an easier installation and lower price, though it lacks the customisability of the technically advanced F2. It's full-auto capable and much quieter than any AEG, making it a great choice to slap in any gun needing a boost in firepower.

F2: For dream AEG builds, the F2 packs unbeatable customisation.
Kythera: For DMR builds, the silence of each shot gives the mechanical Kythera give it a unique advantage.
JACK: If you're new to HPA, the JACK is an affordable older design. It's simplicity means less customisation, but that doesn't hold back its potency.

The nozzle on an AEG gearboxes is never universal, meaning the dimensions can differ depending on both the model and manufacturer. Accounting for this, PolarStar have developed over 20 unique nozzles for their HPA engines, with each nozzle capable of fitting a handful of guns.

To find out which nozzle is right for your next HPA build, we have provided a handy chart in the product description of the F2, Kythera and JACK engines, listing every size of nozzle and the corresponding guns.