211 is directly heated triode thorium-tungsten cathode, can be used for A, B, C class power amplifier. Filament heating Uf: 10 V If: -3.25 A Electrode capacitance Input capacitance: 6 PF The output capacitor: 5.5 PF Cross-Road capacitors: 14.5 PF Static parameters Ua: 1250 V -Ug: --70 V Ia: 100 mA Gm: 3.8 mA / V u (when Ia = 75mA when): 12 RL: 7 KΩ Pout: 10 W Recommended work status (reference value) Class A single-tube amplification (A-F): Typical operating conditions limit parameters...

PSVANE TUBE WR50 is direct-heated type thorium tungsten cathode triode, can be used as class A1 and AB1 amplification.  Typical operating parameter  Heater voltage 7.5 V  Heater current 1.25A  Ua 350V  Grid voltage -63 V  Ia 45 Ma  Internal resistance 4.1K  Amplification coefficient 3.8  Output power 2.4W 

The price is for Matched Sextets(6pcs) Brand new PSVANE Premium ACME Series Vacuum Tubes Model No.: ACME 274B/A274B​ (Replace other 274B tubes directly) Aluminum teflon tube base Factory test&match pair, luxury gift box Warranty: 12 Months A274B Filament heating Uf..................5V If............... 2A Limit rating Anode reverse voltage peak...............1550V Anode current peak .........750mA Recommended work status Anode supply voltage 2 × 500V...

The price is for one pair. we also can provide the matched quad! The price is for one pair. we also can provide the matched quad!   KT66GC/KT66GE The beam power tetrode KT66GC/KT66GE has an anode limit power dissipation of 25W. Use A1, AB1, AB2 class amplification in audio amplifiers. Hot wire heating UH………… 6.3 V IH………… 1.27 A   extreme rating            Tetrode connection Triode connection Anode...

Features: Filament heating Uf: 6.3 V If: 4 A Limit rating Anode voltage: 1250 V Anode current: 125mA Anode dissipation power: 40W Grid current: 50mA Interelectrode capacitor Input capacitor: 5.5 PF Output capacitor: 0.6PF Transfer capacitor: 5.5 PF Static parameter Ua: 2000V -Ug: 2V Ia: 260mA μ(When Ia=20mA): 160