This B&K 747 tube tester has been in my collection for 30+ years. I liked it so much that I bought a second one to take on the road with me on the rare occasion that I had a service call in a client’s home or studio.This tester is in very good condition and includes socket savers in the sockets we used most for audio tubes. By using socket savers the original sockets remain in new condition and if the socket on the saver ever wears our it’s a simple task to remove it and use th...e original socket or install another socket saver.I will include a pdf file of the owner’s manual. This tester was calibrated early in May of this year.