This Radiotron tube is not cylindrical in shape. It is narrow at the bottom and is wider at the top. The glass is silver except for a clear line at the bottom. There are four pins on the base. Handwritten text on small sticker on glass reads "NG". Printed text "RADIOTRON | -UV-201-A | LICENSED ONLY | TO EXTENT INDI- | CATED ON CARTON" is on the base.