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) these are probably the best

these are probably the best E188CC/CV4108/7308 type tube made by Mullard

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

Bottom part is NOS GEC phenolic plug

even more natural midrange

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

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) these are probably the bestNOTE: 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