-This 6AC7-Z made from ShuGuang Electron Group Co.,LTD since 1950s
-ShuGuang's vacuum tube production accounts for the world's 40% total tube output nowadays,
either under their own brand "ShuGuang" or under OEM brands.
-Generic ShuGuang tubes come in clear glass enclosure. The 'ShuGuang Treasure' ® series comes
with carbon compound coating inside the tubes making them appearing to be 'black bottle'. They
are only released in Dec 2008 to celebrate ShuGuang's 50th anniversary and technology advancement.
All of our vacuum tubes are directly come from the Shuguang Electron Group Co., Ltd. HunanChina; it is 100% factory price. No agent, distributor, or any mediators, etc. in between the buying process. All vacuum tubes are passed the strict quantity test of factory of Shuguang. Any tubes are come with a qualified certificate of the SHUGUANG factory.