Trigger Valve Replacement Part Numbers: 647956-00, 64795600, 641011-00, 647620-00 O-Ring Replacement Part Numbers: D51822, D51823, D51844, D51845, Universal O-Ring Kit Type 1, 2, 3, 4, 5 High Compatibility: 647956-00 Framing Nailer Replacement Parts D51256 D51276 D51321 D51430 D51431 D51822 High Compatibility: Compatible with D51238K (Type 1) 2 inch 18 Ga Brad Nailer, D51257K Type 1 16 GA Finish Nailer, D51257K Type 2 16 GA Finish Nailer, D51275 Type 1 Finishing Nailer, D51276K (Type 1) 15 gauge 15 gauge 2-1 2-1/2 inch (about 2.5 cm) Finishing Nailer, D51321 Type 2 Coil Roofing Nailer, D51822 Type 4 Framing Nailer, D51844 Type 4 Framing Nailer, D51855 Type 1 Coil Framing Nailer Use first-class components and strictly adhere to standards. Wear-resistant, stable performance, long service life Colour:As Shown Material:Metal + Plastic Package Contents: 1 * set O-Ring Rebuild Kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.