U525U4GBranded MarconiBaseBlackBottle HeightTall BottleBrand ExtendedThe Marconiphone Co. Ltd.CountryGreat BritainGetterBottom GetterGlass ColorClear GlassMicaDoublePermanentidywbi45h0Pin ColorSilverPlate ColorBlackPlate LookSmoothMore U52 type tubesU52Branded OsramU52Branded G.E.C.U52, 5U4G, CV1071Branded M.W.T.U52Branded MarconiMore 5U4G type tubes5U4GBranded MazdaBelvue5U4GBranded Fivre5U4GBranded Tung-Sol5U4GBranded TriotronU52, 5U4G, CV1071Branded M.W.T.5U4GBranded Fivre5U4GBranded Brimar5U4GBranded Marconi Italiana5U4GBranded Super Silvertone5U4GBranded SicteMore tubes branded Marconi6CA7, XF4Branded MarconiZ729, EF86Branded Marconi12AX7A, 7025AMarconiBranded MarconiECC82, B329, K61MullardBranded MarconiECC83, B339, F91MullardBranded Marconi12AX7Branded MarconiECC83, B339, I61Branded MarconiECC83, 12AX7Branded MarconiB329, 12AU7Branded MarconiECC83Branded Marconi