HP (also known as Agilent or Keysight) 54001A 1 Gigahertz Active Probe with 1.5meter cable and accessories
Great for use with 54000 series scopes! This probe is like new in the original box; it was stored in a commercial electronics lab and I am not sure it was ever used. Comes with original HP Operating Note/manual. Comes with all original accessories seen, including original HP "fiddle stick" (pot/trim cap adjustment tool).
You may want to pull the foam off and discard it because it is falling apart (as with all foam of this vintage), even though this tool was professionally owned and stored well within manufacturer specs in an engineering lab environment.
Input capacitance: 2pF
Max input voltage: 20V