Vintage K40Y-9 Soviet Military Paper in Oil (PIO) capacitor, .033uF 200V. The K40Y-9 are high quality capacitors made for Russian military. The conductor is made of aluminum foil and the dielectric is oil saturated paper. Comparable in construction to the Sprague Vitamin Q's, hermetically sealed in a metal body with glass ends. These capacitors provide excellent sonic characteristics, and a high tolerance within a wide temperature range. These will work in Fender Strats and Tele's as well as in a Les Paul, or Les Paul style guitar on the bridge pickup. .033 is an interesting choice for P-90's. Great way to improve the tone of your guitar, or for use in other audio applications.