Sicce JOLLY PRESET 25 – Submersible Heater – 25 watt Jolly Preset Heaters have an Auto Shut Off feature that automatically turns the heater off when the temperature is reached.JOLLY plastic heaters are designed for small freshwater, marine, and turtles tanks. Their plastic casing makes them very durable and safe. These heaters can be placed beneath the gravel, making them a good choice for a turtle or reptile tanks. JOLLY is always on when submerged. It stops working only when unplugged. The built-in thermal protection intervenes when the heater isn’t underwater, preventing overheating (LED light OFF even if Jolly is plugged in). Performance can vary according to the following parameters: – Quantity of water – Room temperature – Open or closed tankReinforced plastic casing to make it fully submersible and unbreakablePrecise electronic thermometer preset at 25C – 77FRedON – OFF LightStrong Suction cup holderAuto shut off when the temperature is reached