These are NOS, made by Tungsram, in the standard DO-7 case. They have the part number and mfg logo printed on the body. Vf is in the .38-.39 range. 55v, 500mA. These are high quality parts in perfect condition.
They work well but you have to take great care. I bent one of the leads to place it through the pcb and the glass next to the lead on the diode chipped. I bought 4 and needed two for the project but not sure the one that chipped will still work.
