Pulled from working equipment by a professional, personally tested and guaranteed. Please note that my testing is limited to continuity testing. Beyond that these are visually inspected and then guaranteed for money back if not right for you. No risk! This product is a set of two vintage BECKMAN 12AV7 stereo tubes that have been tested and found to be strong. The tubes come bundled together and are a custom bundle. They are not modified and are in their original state. These tubes are suitable for use in vintage electronic equipment.