Russian ultrahigh frequency triode 6S17K-V (6C17К-В) is a tube enclosed in metal-ceramic case. Metal parts are silver plated. This small tube was already used in some of the DIY amp projects with very good results. Its weight is only around 5 g and service life is not less than 2000 operating hours. New old stock tubes in original boxes (please see the gallery). Made in the early 80's.