Polarstar Kythera SA nozzle

PolarStar has been naming their nozzles with numbers instead of gun models since July 2016. This is because the nozzle length can vary between the same gun model when it is made by different manufacturers. The reason for this is the small dimensional differences in the parts used by different manufacturers, and even the thickness of the gear case shell can vary between different manufacturers. For example, a standard MP5 can require any of four different nozzle lengths depending on the manufacturer.

PolarStar maintains an extensive nozzle compatibility chart on their website Help Center page. Check out the compatibility chart here.

Once you have determined which nozzle number fits your airsoft gun, that number is universal across all PolarStar HPA units that use a numbered nozzle system (with the exception of some model specific Kythera systems). So if you determine that your airsoft gun requires nozzle number #11, you should install the nozzle number #11 whether you install a Jack, Kythera or F2 unit.

*ATTENTION:

Kythera nozzles marked with the letter K are designed for specific airsoft guns that use longer cylinders (for example, the A&K/JG SR-25). Since the "K" nozzles are intended for use with unusual cylinders, the general nozzle numbering system cannot be used for these models. However, the "K" nozzles have the same design and profile as the standard numbered nozzles and will fit Kythera air systems in the same way as standard nozzles.

Additionally, all nozzles are marked with their numbers, except for nozzle #1. They are produced in significantly larger quantities than other nozzles, so they are left unmarked to speed up production.