This is a piston pin support plate made by JIMS, a manufacturer of specialty tools for Harley-Davidson. It's a tool used to prevent the piston from dropping during assembly of piston rings, etc. JIMS part number 1164 #HarleyEngine #Piston #HarleyTools This item is unused. We are selling it at a lower price than the market price, so please refrain from asking questions about price reductions.