This is a matched pair of RCA-branded single halo getter & dual side getter NOS 6550's that I purchased from a very reputable tube dealer last year. Very unfortunate circumstances meant that I never took delivery of the amp that these tubes were intended for. Therefore I've decided to sell them. They are 100% unused by myself and I only took them out of the box to visually inspect them, so I can guarantee they'll look good but unfortunately I never got to listen to them. And as a very long time member of Head-Fi I can assure you these will be packaged and shipped appropriately.