This is a used Eimac 3-500Z.I recently testedthis 3-500Zinmylinear amplifier and it delivered full output. I am adding some history on this 3-500Z. In the late1980\'s EIMAC manufactured some 3-500z\'s with defective welds that resulted in the plate falling off the plate cone. This happened to two 3-500Z\'s that Ipurchased from AES. I contacted EIMAC when this happened andreturned the defective tubes to EIMAC and they sent me replacement tubes free of charge.THIS 3-500Z IS ONE OF THE TWO TUBES EIMAC SENT TO REPLACE THE DEFECTIVE TUBES. The metal shield on the inside the tube at the bottom hasJMY061 inscribed in it.The outside of theglass envelopehas the numbers 08594 9305 printed on it.It is sold AS IS withno right of return and shipped only to the continental USA via theUS Postal service.

---