Reliability Provin KT-HA-508 Aftermarket Replacement Part for the Hitachi KT-HA-508 O-Ring Kit This kit will fit the following nailers: Hitachi N5008AA Includes: All the o-rings in the tool. Instructions with a schematic of the tool. O-Rings are color coded to aid installation. Manufacturer: Reliability Provin Part Number: KT-HA-508 This is a brand new tool part and comes with manufacturers warranty.