Installation | Two separate enclosures allow the product to remain sealed for installation. The lower shell is removed by a thumb-screw, revealing spring-loaded contacts for easy connectivity. Note the cut-out on the chassis for entry of concealed or cased wires. Attention to detail includes donuts pressed around the screw mount holes to strengthen the material and protect knuckles from getting grazed on the screws. The pressed indent on the chassis, in the form of an upward arrow, converts an engineering detail into a graphic message for direction of installation.