5951 Black paper "flat-back" tape, 1/4" wide x 65-feet long. Used to wrap humbucker bobbins after winding. Also used to cover solder joints of lead wires.
5952 Black cloth tape, 3/8" wide x 65-feet long. Ideal for wrapping a humbucker after it's been assembled to protect the bobbins. Can also be used with single-coil pickups to protect the windings however, this is not "vintage".
Example: Use conductive foil wrapped around the windings to reduce 60-cycle hum. Wrap the coil with tape, then wrap the #0036 1/4" Conductive Copper Tape over the tape and connect to ground.