The landscape transformers are Hampton Bay's lowest profile slim line power units which can be easily concealed after installation. These units are based on a potted toroidal core design that eliminates annoying buzzing sounds while offering the highest efficiency possible. Our Hampton Bay SL units meet the Department of Energy DOE mandatory requirement efficiency rating of VI. Utilizing state of the art sensing circuits, our transformers provide dual safety functions that detect and react to a system overload or a short circuit condition in a landscape installation. Hampton Bay power packs provide convenient features and flexibility to design simple or more elaborate landscape lighting designs. The transformer includes a photocell and digital timer, a ground shield making it safe for use with submersible lights. The units are equipped with dual voltage output terminals (12-Volt and 15-Volt) which help compensate for voltage drops in high-Wattage / longer wire runs as well as to help reduce cable loss when using 15V LED fixtures.