1. Small Short tube T20 led filament bulb is usually used for lighting, the size is small. Because the size is small, we can not put too much led filament inside, so the wattage and lumen is low. Take this T20 Led filament bulb for example, the size is diameter 20mm, length is 58mm, we can put 2 pieces or 4 pieces maximum 26mm length led filament into this small short tube led bulb, one piece 26mm Led bulb is 0.5W rated, so the maximum wattage we can do is 2W for this T20 Led bulb. This T20 led bulb has 2 pieces of 26mm filament Led bulb, the rated wattage is 1.0W.