Download Installation Instructions Honda CRF PowerFlow kit with Inner Sealing Ring 150212c / 150213c / 150214c Step 1 – Remove OEM inner sealing ring, connection tube, and outside air boot sealing ring. Refer to owners manual. Step 2 – Before installing Twin Air Inner Sealing Ring, apply a bead of silicone sealant into the machined groove on the Twin Air Inner Sealing Ring. Step 3 – Install Twin Air Inner Sealing Ring into the air box, attach air boot, and outer air boot sealing ring. Tighten nuts to clamp airbox together. Optional Twin Air Outer Sealing Ring Available (150212/150214 OSR) Step 4 – When you are finished assembling the airbox, you need to cut off the rubber lip on the inside of the air boot.