Features easy to use 1-button operation, automatic calibration and integral concussion-proof housing. Large LCD simultaneously displays H2S, CO, O2 and combustible gas concentrations. Rugged, compact and lightweight. Datalogging/event logging standard. Audible, visual and internal vibrating alarms with four alarm levels: High, Low, TWA and STEL. Rechargeable lithium-ion battery provides up to 14 hours of operation. Battery recharge time of 6 hours. Durable, stainless steel alligator clip. Highly water-resistant. IntelliFlash™ provides continuous visual confirmation of detector operation and compliance. Yellow