These parts are salvaged from a chassis. I tried to be careful removing tubes, but working condition unknown. I can’t guarantee the performance of these parts, but it was stored inside. I’m going to list chassis as well.

Offered for sale are the 3 tubes as titled and pictured. These particular 3 tubes tests strong and are closely balanced / matched. The tubes’ test results are displayed in the photos (New 5751 Spec 100% = 1,200 Gm). Note: Even though this tube is often considered interchangeable with the 12AX7, the 5751 does have a bit less gain than a 12AX7, so the test results displayed are the actual Amplitrex specs for the 5751. Also, these tubes are labeled Westinghouse and there are no other EIA codes or numbers on them. So far, these boxes are still just a concept and in the prototype stage (3D Printed). Any and constructive feedback on the idea is welcomed and appreciated. Eventually I plan to offer these boxes for sale by. Themselves, but not quite yet. See the photos for physical / cosmetic condition. Notes Regarding Tube Tests. All tubes are tested on an Amplitrex AT-1000 tester in the automatic Fixed Bias Mode (for the most conservative results). Test Results are for a general reference only, and are not a guarantee of performance, nor a guarantee of how they will test on your tester. No real world (audio) performance measurements are taken.