Mcquay International Wall Sensors P/N 058899341. These are Gen1 McQuay Microtech wall sensors these were working pulls from an upgrade project. They were originally paired with Microtech 325 Controllers in unit vents. They are in good condition but may show signs of wear or markings consistent with a used controller. They are sold as is, but we do basic testing by powering them up and visually inspecting them before shipping.