Check the listing for details. 6N23P Voskhod 1971. MATCHED PAIR. SWGP. Grey Shield NOS/ ECC88 6922.. Condition: New. Listed at 69.00 USD. MATCHED Balanced PAIR Voskhod 6N23P. (Equivalent E88CC / 6922 / 6DJ8). GREY SHIELD.NOS RARE DATE CODES 1971 YEAR. SWGP (Single Wire Getter Port) SWGP Silver Shield 6N23p (ECC88 6DJ8 E88CC 6922) Made by VOSKHOD factory (ROCKET logo, city Kaluga USSR) in 1973. The parameters are measured at Uf = 6.3 V, Ua = 90 V, Bias voltage = -1.3 V Tubes 6N23P in store:PAIR 6N23P Reflektor Silver Shields 1975 https://www.ebay.co.uk/itm/387328662706PAIR 6N23P Voskhod Grey Shield 1975 https://www.ebay.com/itm/387365992798PAIR 6N23P Reflektor Silver Shields 1974 https://www.ebay.com/itm/387545088495PAIR 6N23P Reflektor Grey Shield 1974 https://www.ebay.com/itm/387365953198PAIR 6N23P Voskhod Grey Shield 1974 https://www.ebay.com/itm/387419781295PAIR 6N23P Voskhod Grey Shield 1973 https://www.ebay.com/itm/387498918749PAIR 6N23P Voskhod Grey Shield 1972 https://www.ebay.com/itm/387503089436PAIR 6N23P Voskhod Grey Shield 1971 https://www.ebay.com/itm/387572827084