Details
New old stock octal half wave rectifier with top cap. 1B3GTs are shorter than 8016s. The GTA versions are the shortest. Various brands.
NSN/FSN = 5960011330027, 5960000271731, 5960005534504, 5960001935087, 5960005576889, 5960005788774, 5960007525270 (1G3GT), 5960007525270 (1G3GTA)
Tektronix Number = 154-0091-00