This set of four programmable electronic temperature controllers operates on a 12V power supply and is designed for precise temperature management across a wide range from -50 to 110 degrees Celsius. Each unit functions as both a heating and cooling thermostat control switch, allowing users to set desired temperature thresholds and hysteresis parameters. The controllers utilize a built-in NTC waterproof sensor probe, which ensures accurate readings in humid or submerged environments such as aquariums, hydroponic systems, or incubation setups. The dual-color LED display monitor provides clear visual feedback, with distinct colors indicating heating or cooling status at a glance. The module's compact enclosure is made from durable flame-retardant ABS plastic, offering reliable protection against electrical shorts and physical impact. Internal components are soldered with quality control, ensuring consistent performance under continuous operation. The device supports programmable on/off delays and temperature calibration, giving users flexibility to fine-tune operations for specific requirements. With a straightforward interface, the controller can be easily configured using a few buttons, making it accessible for hobbyists and professionals alike. Its compact size allows for convenient mounting in tight spaces, and the included wiring terminals simplify integration into existing systems. The four-piece kit presents a practical solution for multi-zone temperature control, reducing the need for multiple separate purchases. Each controller is pre-calibrated at the factory, though users can manually adjust offset values if needed. The waterproof probe features a silicone-sealed cable resistant to moisture ingress up to 5 meters depth, enhancing reliability in wet conditions. This product is suitable for applications such as reptile terrariums, fermentation chambers, seed germination mats, and small greenhouse climate management. While not intended for medical or life-supporting systems, it provides dependable temperature regulation for common DIY and light commercial projects. The dual relay configuration supports both normally open and normally closed modes, enabling fail-safe operations.

This kit offers a cost-effective way to achieve precise thermal control without sacrificing durability or ease of use.