1. Cylinder led bulb is also called tube led bulb, because cylinder glass globe is also called glass tube. This cylinder led bulb has a glass tube of 300mm length, 30mm diameter, the thickness of the glass is more than 2mm. The cylinder glass tube is made of high quality glass, it is much strong than normal quality glass. Two piece of 255mm length flexible soft led filament forms a hairpin filament design, which is also a classic vintage light bulb filament design.