The EHEIM Jager TruTemp Fully Submersible Aquarium Heater, with a power rating of 100W, offers a range of features tailored for efficient and precise temperature control in both freshwater and marine setups. Its thermo safety control prevents overheating by shutting off when out of water, while the shatterproof glass construction ensures durability. The heater is fully submersible and waterproof, with an extra-long cable of 5'6" for convenient placement. It includes a clamp with two suction cups for secure attachment and a TruTemp dial with a re-adjustment ring, allowing users to calibrate the heater for precise temperature regulation. This model is suitable for aquariums up to 40 US gallons.