MULLARD CV4033 - Very rare 1958 - Mil wrinkle glass, Halo GT. - Whyteleafe "A" Production Prem. Grade Long Life ECC81:CV4024:12AT7 Factory Tested (Plug&Play Ready to Use) 12Axx to 6SL7/6SN7 adapter will

12Axx to 6SL7/6SN7 adapter will let you use common tubes like 12AX7/ECC83

MINT NOS NIB Rare 1961 Mullard CV4035 M8214 Box Plate Wrinkle Glass Military production

Bottom part is NOS GEC phenolic plug

Early 1956 BRIMAR CV4033 with Square Getters

I run them in my Mcintosh MC-2000 in the V2 position (input/phase inverter)

MULLARD CV4033 - Very rare 1958 - Mil wrinkle glass, Halo GT. - Whyteleafe "A" Production Prem. Grade Long Life ECC81:CV4024:12AT7 Factory Tested (Plug&Play Ready to Use) 12Axx to 6SL7/6SN7 adapter willNOTE: After spending $$$$ on tooling and various prototypes, we have fitted Special Grade Flying Leads tubes with Custom Thermo setting Bases developed in house. It is a multi step, labor intensive process. Each lead is straightened and cleaned to ensure perfect fusion with the base pins in the silver soldering bath. Process is painstakingly slow, so we will be adding a few tubes at a time to the inventory. Tubes are Plug & Play, Ready to Use. Brand