HP USB cable 8121-1209 connects a device with a USB Type-A port to one with a USB Type-B port. It is listed as an HP spare part for printer product series.
The cable has a male 4-pin USB Type-A connector at one end and a male 4-pin USB Type-B connector at the other. Its 1.0 m length provides a short wired link between compatible ports, useful for connecting a printer to a computer or another USB host with a matching Type-A connection.