Quality vintage soviet ceramic tube sockets PLK9-D55 (ПЛК9-Д55) for miniature 9-pin tubes. Sockets are equipped with removable steel retainer. It is suitable for tubes like 6N6P (6H6П), 6P1P (6П1П), 6E6P (6Э6П) and many others. After very easy removal of the retainer they may be used for all noval tube types. New old stock.