There are a few types of Tubular Heaters with different power ranges to each.
Screw-in tubular heaters with threaded plug for heating liquids.
Power range from 1000 W to 12000 W
(Standard applications include the heating of recycled water for sanitary services, chlorinated water, demineralized water, fuel oil, mineral oil on the basis of the specific load)
Screw-in tubular heaters are electro-thermal sets equipped with threaded plugs to heat up liquids.
Power applications range from 2000 W to 35000 W
Screw-in tubular heaters with threaded plug for heating liquids.
Power range from 1000 W to 6000 W
Find out more about what are immersion heaters?