Can be used for power triode parmeko partridge gresham freed c-core transformer cho ke amp as : 300b, 2a3, 45, 46, 50, VT-52, 300B, 101D, 205D, R120, VT25, 10Y, RS242, E130 SFR, PTT3, PTT205...
Nice for single ended tube amplifier , push pull, audio or r adio
Tests: Tube 1: 8,4/7.7mA 3.6/3.6mA/V fabrication code: U605904 252551 U.av.01 L 143 Tube 2: 7.8/8,2mA 3.5/3.6mA/V fabrication code: U605904 252551 U.av.01 L 143 Considered as NOS when test 8.0/8.0mA 3.6/3.6mA/V Test on Metrix U61 instrument