Check the listing for details. BN-LINK / BNQ-T7B(H) / Digital Heating Temperature Controller 125V 60Hz TESTED. Condition: Used. Listed at 14.90 USD. This BN-LINK Digital Heating Temperature Controller Unit is a top-notch product that will exceed your expectations. With a compact size of 6 inches in diameter and made of high-quality plastic material, it will blend seamlessly with your hydroponic systems. The controller unit has a single outlet and features a digital display that is easy to read and operate. It comes with a set that includes a controller unit to ensure that you can start using it right away. The BN-LINK Digital Heating Temperature Controller Unit is perfect for hydroponic enthusiasts who want to maintain a consistent water temperature in their systems. It boasts top-notch features, including a heating temperature controller with a voltage of 125V and a frequency of 60Hz.