Early 6SN7GT (CKR-6SN7GT) has the WWII era blacked glass. These are military grade tubes and are guaranteed to improve the sound of your system. New Old Stock (Marked with E3) No longer available for export MFR: RCA (US Navy) SKU: 6SN7GTB-RCA-BG
Designed for use in resistance coupled circuits as a voltage amplifier or phase inverter. The TungSol 6SL7GT round plates are considered by some to be the best 6SL7 tubes available.
New old stock * No longer available for export. MFR: Tung-Sol SKU: 6SL7GT-TS
Designed for use in resistance coupled circuits as a voltage amplifier or phase inverter. Black base and band on glass. MFR: Standard Brand SKU: 6SL7GT-SB New old stock * No longer available for export.
Designed for use in resistance coupled circuits as a voltage amplifier or phase inverter MFR: Sylvania SKU: 6SL7GT-SYL New old stock * No longer available for export.
Designed for use in resistance coupled circuits as a voltage amplifier or phase inverter New old stock * No longer available for export. MFR: RCA SKU: 6SL7GT-BRN-RCA
Designed for use in resistance coupled circuits as a voltage amplifier or phase inverter New old stock * No longer available for export. MFR: RCA SKU: 6SL7GT-BRN-RCA