The replacement part number is N866410 N816252 N880093 N851276 N882713 NA039663 NV039663. 2、It fit to 20V DCF899 TYPE 4 Cordless Impact Wrench. It fit to 20V DCF899 TYPE 4 Cordless Impact Wrench. Compatible with: DCF899B Type 1, DCF899B Type 3, DCF899M1 Type 1, DCF899M1 Type 3, DCF899P1 Type 1, DCF899P1 Type 3, DCF899P2 Type 1, DCF899P2 Type 3. The item is fit to Dewalt DCF900NT，DCF900P1 20V MAX Cordless Impact Wrench Kit，DCF900N 20V MAX 1/2" BRUSHLESS Cordless Impact Wrench，DCF900B 20V Cordless 1/2" Impact Wrench，DCF900GP2 20V MAX XR 1/2-in Cordless Hog Ring Anvil Impact Wrench，DCF900 18v xr 1396nm 1/2" brushless HOG RING impact wrench. Size(LxD): About 2.123x0.709 inch,It must be checked for the size, the Anvil Assy have different size.Replacement part# N866410 N880093 N851276 N415875 N882713 NV039663 It must be checked for the size, the Anvil Assy have different size.Compatible with: DCF899B Type 1, DCF899B Type 3, DCF899M1 Type 1, DCF899M1 Type 3, DCF899P1 Type 1, DCF899P1 Type 3, DCF899P2 Type 1, DCF899P2 Type 3.it fit to 20V DCF899 TYPE 4 Cordless Impact Wrench.this kit is ift to Dewalt Impact Wrench Kit 1/2 Anvil,chuck Replacement,Detent Pin Anvil,Driver Spindle Hammer Block For DCF899 DCF899B DCF899M1 DCF899P1 DCF899P2 type 4 Impact Wrench