Due to increased demand, orders which contain an HPA SYSTEM or AIR SYSTEM may take up to 1-2 weeks to ship. Please see our DEALER LOCATOR for a list of authorized dealers which may have stock available for immediate shipment.

Help Center

New to HPA?

So, you're interested in trying out this HPA thing but want to find out more but want to find out more before you take the leap. Check out our FAQ to better understand the basics of what is needed to make a conversion possible.

Will a PolarStar HPA conversion fit my rifle?

It can be frustrating to purchase upgrades only to find out that they don't fit your particular rifle. To make things easier we have compiled a database of information on compatibility of the various PolarStar HPA conversions into a wide range of models.

What HPA system do I choose?

Gearbox Version - The first step in selecting an HPA conversion kit is to determine which gearbox "version" your AEG uses. Over the years, AEG manufacturers have created various gearbox versions suited to the shapes of different real firearms. In the case of our cylinder conversion kits such as the F2, the gearbox version will determine what switchboard model will be required to interface with the trigger and selector components. Since the Fusion Engine replaces the entire gearbox the "version" will determine which Fusion Engine model can fit into the replica.

Nozzle Type - It is important to know whether the nozzle of the AEG is centered in the cylinder (V2, V3, M249, etc..) or if it is offset vertically (M14, SVD). This will determine which HPA systems are compatible with your AEG. At this time, only the F2 supports AEGs with offset nozzles. Offset nozzles have a "O" prefix before the number.


Why do most of the nozzles have numbers instead of the rifle model?

For cylinder conversion systems we assign numbers to the nozzles instead of using the rifle model. This is because the nozzle length can vary between the same gun model when made by different manufacturers. This can be from the manufacturer designing the rifle differently, or from the thickness of the gearbox shell affecting how far from the hop-up chamber the cylinder sits. Therefore one nozzle length may work in different rifle models but not necessarily work in the same model from a different manufacture. For example, a standard MP5 could require any of 4 different nozzle lengths depending on the manufacturer.

For this reason we produce numerous different nozzle lengths to provide compatibility for a wide range of replicas. Although you might see our nozzles being listed with the gun model which the nozzle length is most commonly used with in the title, it is typically compatible with more that just that model.

Model Manufacturer Gearbox JACK F1 F2 Kythera SA Fusion
AK G&G V3 2 2 2 2 AK
AK CYMA V3 2 2 2 2 AK
AK Tokyo Marui V3 2 2 2 2 AK
AK Real Sword V3 9 9 9 9 N/A
AK E&L V3 9 9 9 9 N/A
AK LCT V3 12 12 12 12 AK
AUG Classic Army V3 17 17 17 17 N/A
Beretta ARX160 Competition Elite Force V3 MOD 10 10 10 N/A N/A
Beretta ARX160 Elite Elite Force V3 MOD 10 10 10 N/A N/A
CZ 805 Bren ASG V3 14 14 14 14 N/A
FAL King Arms V3 6 6 6 6 N/A
G36C (S&T / ARES) Elite Force V3 MOD 16 16 16 N/A N/A
G36K Classic Army V3 20 20 20 Special Order G36
G36KV (ARES) Elite Force V3 MOD 15 15 15 N/A N/A
HK417 Elite Force HK417 1 1 1 N/A N/A
KAC LMG Classic Army KAC LMG 11 11 11 N/A N/A
M14 G&G V7 N/A N/A O-1 N/A N/A
M14 CYMA V7 N/A N/A O-5 N/A N/A
M240B Echo 1 M240B 6 6 6 N/A M240
M249 Classic Army MG 3 3 3 N/A M249
M249 / Mk46 G&P V2 2 2 2 2 N/A
M249 Featherweight Cybergun V2 14 14 14 14 N/A
M4, CM Series G&G V2 1 1 1 1 M4
M4, ES Series VFC V2 1 1 1 1 M4
M4, GC Series G&G V2 1 1 1 1 M4
M4, CXP Series ICS ICS V2 2 2 2 2 N/A
Masada A&K V2 13 13 13 13 A&K SR-25
Mk43 (M60) A&K MG 14 14 14 N/A M60
MP5 A/SD Series Tokyo Marui V2 1 1 1 1 M4
MP5 A/SD Series (Blowback) G&G V2 18 18 18 Special Order M240
MP5 A/SD Series ECHO1 V2 2 2 2 2 MP5
MP5 A/SD Series CYMA V2 2 2 2 2 MP5
MP5 A/SD Series JG V2 2 2 2 2 MP5
MP5 A/SD Series (3pos Selector) VFC V2 Avalon 11 11 11 11 AK
MP5K-PDW Series CYMA V3 21 21 21 21 N/A
PKM Echo 1 MG 1 1 1 N/A M249
SCAR-H VFC V2 8 8 8 8 SCAR-H
SCAR-L VFC V2 1 1 1 1 M4
SCAR-L Classic Army V2 7 7 7 7 N/A
SIG 552 ICS V3 5 5 5 5 N/A
SR-25 A&K V2 LONG 5 5 5 K1 A&K SR-25
SR-25 JG V2 LONG 5 5 5 K1 A&K SR-25
SR-25 (GR-25) G&G V2 4 4 4 4 G&G SR-25
SVD Real Sword RS T3 N/A N/A O-8 N/A N/A
Stoner 63 / MK23 MOD 0 G&P V2 11 11 11 N/A N/A
Tavor Competition (S&T) Elite Force PROP 9 9 9 N/A N/A
Tavor Elite (ARES) Elite Force PROP N/A N/A N/A N/A N/A
UMP Elite Force V3 MOD 15 15 15 N/A N/A
UMP G&G V3 2 2 2 2 N/A
XCR (VFC OEM) Echo 1 XCR 19 19 19 N/A N/A