Here we have (4) RCA 6550 Metal Base Vacuum Tubes. Branded wirh LESLIE on bases.

Tested on an Amplitrex for fixed and auto bias. Listened to for quality if sound. Tubes tested 85-90%. All tubes passed gas test.

YUP. Ugly getters. I think all 6550s have this. Not gassy. Amplitrex passed gas test.

Please see my other listings for many more great tubes.