PolarStar F2 SR25 A&K

Product content :

- Polarstar F2 V2 SR25 A&K
- FCU wire harness    
- FCU REV3    
- V2 Trigger board    
- English Manual

What is F2?

F2 is essentially a Mini Fusion Engine. It offers the same adjustability and performance as the Fusion Engine in a cylinder sized package.

Patented Dual Solenoid Design

The dual solenoid design of the F2™ provides the same functionality as the legendary Fusion Engine™ but in a more compact, efficient and flexible design. Dual solenoids allow for the nozzle and the poppet valve to be adjusted independently of each other for unparalleled control over both the loading time and air volume used. Additionally, this makes it possible to change the firing sequence giving it the ability to operate in both true closed bolt as well as "AEG" mode.

Increased Efficiency

The F2™ incorporates a new one-piece, lightweight poppet valve design yet still operates on the same principle as the Fusion Engine™ poppet. This valve is able to operate at lower pressures and uses less air volume to function which optimizes air efficiency. The standard F2 poppet is equivilent to the Red Low-Flow poppet of the Fusion Engine.

Spring Loaded Nozzle

The F2™ nozzle is spring biased forward which provides a consistent loading force regardless of operating pressure. It shares the same spring as the Fusion Engine™ with both light and heavy spring options available to adjust the loading force. The robust design of the F2™ allows for an operating pressure range of 45psi to 145psi which enables it to achieve velocities from CQB to DMR while employing only one nozzle for the entire velocity adjustment range.

What is the difference between F2, F1 and JACK ?

Both F1 and JACK are "open bolt" systems, meaning the nozzle is in the rearward position when the system is idle and the round is fired during the forward movement of the nozzle. F2 is a dual-solenoid system which allows for complete control over the shot cycle

Nozzles :

Over 20 standard F2 nozzles are available for installation into a wide range of replicas. These are numbered, rather than named, since a single nozzle is often compatible with multiple replicas. The "Original Model" listed in the table is the replica from which the nozzle measurements were taken and is for reference. If your gun is not listed in our Compatiblity Database a recommended nozzle length may calculated by measuring your original gearbox and applying the following formula: TIP = F + B - (A/2) - .057. A more precise measurement (which accounts for the hopup and bucking in use) may be obtained by installing a nozzle into the system which is slightly too long for the replica and measuring the nozzle setback when placed into the hopup.

Options available in the future :

    Offset and Centerline cylinders and nozzles.
    Wire harnesses are available in 7.5", 13" and 18" standard lengths
    Interchangable Bushing Inserts which prevent any movement of F2 within the gearbox.
    Custom nozzle lengths available.
    Low velocity poppets (< 1J) available.
    Light and Heavy nozzle springs available.

Please note that instaling a HPA drop in system is recommanded for skilled gunsmith only. The product comes as a spare part and does not come with installation manual. By purchasing an HPA system you take entire responsability of the assembly and upcoming results. For products delivered with a trigger board, contactors / switch are not guaranted by the manufacturer in case of break. We advice to take extreme care when installing the selector plate in order to not break the button. Regarding the trigger switch, it is recommended to block mecanicaly the trigger once the the trigger switch is activated to avoid excessive pressure on it.