ALTAIR® Disposable O2 Single Gas Detector. Features sensor options for O2 and will operate for over 2 years. Superior dust and water protection are accomplished due to the rubberized housing, while the 1-button operation provides durability and ease-of-use. Triple alarm system features two bright LEDs, an audible alarm and a vibrating alarm that ensures no alarm condition goes unnoticed. Automatically records the last 25 alarm events. Utilizes fast responding reliable electromechanical sensors.