Designed to operate in radio frequency or intermediate frequency amplifiers in battery operated receivers. New old stock * No longer available for export. MFR:Standard Brand, Philco, RCA, Radio Television. SKU: 1U4
Designed to be used in relay and grid-controlled rectifier applications. New old stock * New In Box * No longer available for export. MFR: RCA, Westinghouse, Sylvania, GE, Tung Sol, National SKU: 2D21