The QRAE 3 is a durable and versatile diffusion or pumped one-to-four gas monitor for detectionof combustibles, oxygen, hydrogen sulfide, carbon monoxide, sulfur dioxide and hydrogen cyanideand other gases. Standard features include easy-to-change battery packs, easy access to sensors,internal vibrating alarm, loud 95dB audible alarm, and a water-resistant IP-65 case design.The rechargeable Lithium-ion battery delivers up to 14 hours of continuous operation innon-wireless diffusion mode. Base: PGM-2500 Series Pump & Diffusion: QRAE 3 - Pump Certification: Custom Union Wireless: no-wireless Socket1 Sensor: LEL (0 to 100% LEL, 1% res.) Socket2 Sensor: NH3 (100 ppm, 1ppm res.) Kits: Accessory Kit