NOS Do you want more power in that late model RZR? NOS now offers complete kits that add up to 40+ HP at the flip of a switch. These kits include the mini 2-stage controller (15974NOS) for exceptionally smooth power delivery. The 5/16" billet fuel rail adapter provides fuel to the billet nitrous plate. These easy-to-install engineered systems do not require any modifications to the fuel system or induction system. Choose from kits w/ different bottle sizes (2.5 lb., 5 lb., or 10 lb. bottle size) and components in the classic NOS blue or new black finish for a stealth appearance.