SIGNODE AMPT-58 or AMP1-34 PNEUMATIC STEEL STRAPPING TOOL for 5/8" or 3/4" STRAP SIZE. I don't know what model strapping tool this is, however, it does have the following model 85R15 stamped on it, which according to a Google search is the Air Motor part and is associated with the AMPT-58 or AMP1-34 model Signode strapping tool. It also has 5/8-3/4 etched on it (see photos). While this information is deemed reliable, it is not guaranteed. If you are not sure what model this is, or feel this information is incorrect, then please contact me prior to purchasing.