The BU-20431 is an insulated, plug-on hook plunger with a standard, right-angle 4mm banana jack. Useful for making test leads which use shrouded, unshrouded, or retractable 4mm banana plugs compatible with connections requiring a plunger clip.
The BU-1162-R is a test lead with a sheathed, right-angle 4mm banana plug on one end of a rubber-sheathed, 18 AWG wire, with a plunger clip on the other end.
Mueller's BU-2741-R is an 8-32 threaded test probe to an unshrouded, right-angle 4mm banana plug. Constructed with EPDM rubber-jacketed, 18 AWG test lead wire.