Automatic constant temperature and high temperature protection. USB plug can be connected to the mobile phone charger or the charging bank. External temperature regulation, temperature control range: 15-34. Quartz explosion-proof material is safe to use. Small size, 52mm long heating rod, as big as the thumb, more beautiful. The water level can be as low as 2cm and can be used by both fish and turtles. It can be used in fresh water, seawater fish tanks, pet feeders, etc. Product name:Mini heating rod Length of power line:1.3m Scope of use:small fish tank/pet water dispenser Temperature control range:15-34 Input power:5V 2A Suitable for:about 2L water capacity Note: Be sure to use 5V2A charger for power supply. If you use a charger with insufficient current, the flash screen will not be heated. This product is suitable for 2L water capacity. Two heating rods can be used in one fish tank to increase the heating capacity, for example, two heating rods can be used simultaneously in a fish tank with 4L water capacity. However, only one heating rod can be used at the same time when one charger or power pack has multiple USB ports, otherwise it will cause heating failure or poor heating effect. Product power: 10W/15W Colour:As Shown Material:Plastic Package Contents: 1 * Fish Tank Mini Heater(without adapter) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.