Electro Harmonix 300B Power Vacuum Tube

This tube mirrors the original Western Electric 300B, featuring an eight-coil, directly heated filament and 40-watt plate dissipation. It showcases the signature large-shoulder glass design and is offered individually, in precision-matched pairs, or quads when available. Each tube’s bias current has been tested and confirmed, with measurements displayed on top of the box under: Plate Voltage – 300V, Grid Bias –61V, Cathode Voltage – 5V AC.