RG BK-R2 NAI Fork kit.
BK-R2 Front fork NAI upgrade. What is NAI?
NAI simply short for No Air Inside. This upgrade for your front forks ensures simple hassle maintenance. When replacing the fork oil simply fill and screw the cap on, they do not require bleeding and they cannot be over filled. The NAI system uses a secondary floating piston at the bottom of the lower legs, improving the performance and handling of the front end.