One QUAD of RCA black plate Holy Grail 6L6GC tubes from the 1960's. These are lightly used very clean tubes with excellent silvering and tightly matched at NOS specs. We've auditioned them in our amp and they perform excellently together with a wonderful vintage sound! These are bright and clear tubes with nice detail, a smooth bass and superb vintage TONE!Brand on tube RCA Actual mfr RCA Country of mfr USA Plate style Black Getter style side "O" Glass style short bottle. Date codes BW, AZ, BS, ?? This item is in the category "Musical Instruments & Gear\Guitars & Basses\Guitar Amplifiers". The seller is "hmb3823" and is located in this country: US. This item can be shipped worldwide.