4 Foot T8 with G13 end caps. The pin to pin spacing of the G13 end cap is 13mm. Up to 1800 Lumens output. Power is 12-36 Volts non polarized DC. Power is applied to G13 end caps at both ends. You have to bypass or remove the ballast and any voltage greater than 36 volts. Available color is Daylight White 4000K. The viewing angle is 120 degrees. The tube is not dim-able. The tube will provide maximum brightness anywhere in the voltage range of 12 to 36 Volts. The Maximum amperage is 1.88 Amps. The tube is made of 1/2 aluminum and 1/2 frosted plastic lens. There are 120 pcs of 2825 SMD led chip for the best illumination possible. PF>90. The diameter is 26mm and the length is 1.2m or 4 foot. This bulb is comparable to a 160 Watt incandescent light bulb but only uses 18 watts. The rated life is up to 30,000 hours. This product is a Non Cancelable, Non Returnable, Non Warranty product NCNRNW. This is due that the low voltage tube can be installed in a fixture with a ballast and causes the tube to fail due to over voltage. Each tube is tested before shipping. CE certified. Comes one tube per package.