I have 20 pair of GE 5 Star triple mica 5751. Must have been pulls. Lettering is just about perfect. I will test them with my Sencore Continental 150. I would expect from their condition. All will probably be well matched. I will try them out in a small guitar amp head, for microphonics and gain. But these were such well made tubes, I doubt any problems. May have a Marantz PM74D. I will also test assorted 12AU and T7's. Have several matching pairs. If anybody need anything else, PM me. I will see what all I have. Sent from my SM-N900V using Tapatalk