Specs

     RF frequency: 868MHz
     Measurement range: 0 ~ 450ppm
     Concentration alarm: 30 ~ 999 ppm
     Response time: <3 minutes for 300ppm concentration, 10 ~ 40 minutes for 100ppm concentration, 60 ~ 90 minutes for 50ppm concentration
     Siren sound power of 85 dB at 1 meter
     Power supply: 3 AA 1.5V alkaline batteries
     Battery life of more than 10 years
     -10 ° C ~ + 45 ° C operating temperature
     Operating humidity up to 85% (non-condensing)
     Dimensions: 130 x 100 x 41 mm