Up for sale is a matched pair (2 pieces) of prime vintage NOS Telefunken EF41 AF/RF pentode vacuum tubes, packed in white boxes. Manufactured in Germany, these tubes feature Telefunken’s desirable round grey plates, a prominent top ring getter, and exceptionally clean glass construction with crisp diamond-logo pedigree. Telefunken EF41 tubes are legendary for their ultra-low noise floor, exceptional transparency, extended high-frequency clarity, and long service life in high-end audio preamplifiers, tuner circuits, and vintage radio equipment.

Both tubes have been tested on an Amplitrex AT1000 automated valve tester at standard factory reference conditions (Ia = 6.0 mA,  Gm = 2.2 mA/V. Anode Current (Ia), Mutual Conductance (mA/V / uMhos), and percentage performance relative to reference specs are detailed in the table below.