A 500k Ohm type B potentiometer with an integral double pole single throw (DPST) push pull switch for electric guitar
The potenitiometer is type B (linear) used for guitar volume control.
This is a miniature potentiometer with a slotted splined shaft as used on many modern guitars.
Use this for customising your guitar without making more holes.
Simply replace an existing potentiometer with this one to incorporate a switch for pickup coil invertion etc.