This heater is controlled by a an adjustable thermostat.Flexible springs are used to attach the silicon heater around various diameter drums. The springs can stretch up to about 3 inches.For plastic drums, it is recommended to keep the thermostat set below 100°F (37°C). Keep your drums,barrels,buckets,pails and gas cylinder propane tanks warm in bitter climates so that you don't lose any production time, saving you both time and money. Size : 200L/125*1740mm/1KW 200L/250*1740mm/2KW 200L/250*1740mm/3KW Specification: Room temperature resistance: 24.2 (Ω) Heating Power:2000W Voltage:110/220V Insulating materials: the maximum temperature of 302 °F (150°C) Insulation resistance: ≥5 MΩ Compressive strength: 1500v / 5s Power deviation: ± 8% Withstand voltage: > 5 KV Main use: heating and heat tracing Package includes: 1* Silicon Drum Heater