GE Canada NOS NIB 5881- Branded as CEI (Calvert Electronics) but made by GE side getters, punchy full tone! These NOS matched pairs and quads of 5881 are just right for that old tweed guitar amp or Hifi! Vintage TONE at a great price!Just $149.99 per matched pair! This is a suitable replacement for any 6L6 tube type. Various brands available.