Add to Cart Quick view Cetron Pair of 4B32 Rectifier Tubes for the Collins KW-1 and Johnson KW Desk Amplifier NEW in Boxes (Replaces the Mercury Vapor 872As) Cetron MSRP: Now: $99.99 Was: This Cetron Pair (2) of 4B32 Rectifier Tubes, are used in the Collins KW-1 and Johnson KW Desk Amplifier. They are NEW in the Boxes and Replace the Mercury Vapor 872As which can cause problems. I have only a few sets left. MSRP: Now: $99.99 Was: Add to Cart Quick view Qty in Cart: 0 Quantity: Decrease Quantity: Increase Quantity: Price: MSRP: Now: $99.99 Was: Subtotal: Add to Cart