KR Audio 842VHD - Low Frequency, high power triode. 12-22 Watts of pure class-A power. Maximum Plate Voltage 600 V Maximum Plate Current 150 mA Plate Dissipation 65 Watts Va 450 V Ia 100 mA Vg -94 V Transconductance 5.7 mA/V Amplification Factor 3.7 Filament Voltage 5 V (DC/AC) Filament Current 1.8 A SPECIAL ORDERED ITEM.THIS ITEM IS MADE TO ORDER.ALLOW 4 TO 6 WEEKS DELIVERY AFTER INITIAL ORDER.