This detector provides fast, reliable information for CO or H2S gases while reducing maintenance costs. The single unit gas detector is user-friendly and affordable. It can be clipped to your pocket, belt or hardhat. Key features include: lightweight (4.1 oz.), compact design, easy 1-button data entry, (3) alarm indicators: vibrating, audible (85 dB) and visual, long-lasting lithium battery. Intrinsically safe rated, CSA (US) - Class I, Groups A, B, C, D; T4A. Ships Direct F.O.B. Mfg. ** PE** 3M Warning GD-1