Big River Hardware creates this Hand turned, solid Illinois black walnut radio pinch knob reproduction. This knob measure about 1 -3/16 inch diameter and 3/4 inch tall. They have been sanded and finished with a French polish. Each knob comes with a half moon / Circle D Steel spring fastener which fits a 1/4 inch flattened shaft common in Zenith Radios. models: 4B231, 4F227, 5F233, 5F251, 5J217, 5J247, 5J255, 5R216, 5R226, 5R236, 5S218, 5S220, 5S222, 5S223, 5S228, 5S229, 5S237, 5S250, 5S252, 5X230, 5X248, 5X274, 6D219, 6D221, 6J230, 6J247, 6J255, 6J257, 6S203, 6S222, 6S238, 6S239, 6S241, 6S275, 6S330, 6S361, 7D203, 7D222, 7D223, 7D229, 7D239, 7D241, 7D243, 7D253 Contact us if you want another type of POT fastener for your electric guitar, tube amp or Fuzz box. Quantity 1 Material : Black Walnut Natural walnut color and grain pattern may vary from the photo Send us a photo if you need a custom knob made . We carry a variety of Illinois hardwoods and can carve any design, logo or letter.