RUFFNECK Defender XT‑311 and XT‑312 explosion‑proof heavy‑duty thermostats are the smallest, lightest and most durable thermostats available. These thermostats are designed to control heating only, cooling only or ventilation systems in demanding industrial applications. These include oil refineries, petrochemical plants, pulp and paper mills, coal mines, grain elevators, hazardous waste storage facilities and other hazardous locations where specific explosive gases or dust are present. For hazardous‑location temperature controls, rely on Defender thermostats for the most dependable and trouble‑free service available. RUFFNECK Defender XT‑311 and XT‑312 thermostat’s unique and highly engineered design offers outstanding features and benefits. Color: Aluminum Gray.