The Walthers Proto 920-584408 is a replacement geared driver assembly for HO scale diesels, supplied as a package of two fully assembled diesel wheelsets. These are the correct replacements for early PROTO 2000 Alco FA, EMD BL2, GP7, GP9, GP18, GP20, GP30 and GP60 locomotives, along with PROTO 1000 EMD F3, Alco RS2 and RSC2 diesels.The units these fit were produced before 2005. Keep a favorite locomotive running by installing the 920-584408 in place of worn or damaged wheelsets, restoring smooth, reliable operation to your early PROTO 2000 and PROTO 1000 diesels.Key Features:- HO scale (1:87) replacement geared driver assembly (diesel wheelset)- Walthers Proto item 920-584408- Package of two fully assembled wheelsets- Fits early PROTO 2000 Alco FA, EMD BL2, GP7, GP9, GP18, GP20, GP30 and GP60- Also fits PROTO 1000 EMD F3, Alco RS2 and RSC2 diesels- For units produced before 2005