Aluminum Housing Armored Cable Contact, SPDT, Higher Security, Wide Gap, Biased for Higher Security Applications, 3/4″ to 2 1/2″ Gap Size, Single Pole-Double ThrowThe 2500 Series is designed to be installed in commercial and industrial environments where a rugged sealed unit is required. It is ideal for metal doors, overhead doors, fences and gates. Each model features a high strength extruded aluminum housing and is completely encapsulated in our exclusive polyurethane potting compound. The 2500 Series feature wide gap distances and several models to meet almost every application need.