1.Available for CO(carbon monoxide). 2.Alarm level: 150PPM. 3.Wall mounted;easy to install. 4.Be able to work with electrovalve. 5.MCU Processing adopted, 6.Malfunction auto-check indicator, 7.SMT manufacture technology ,High stability. 8.Alarm output:Sound&Flash alarm; 9.Operating voltage: 85V-265V AC; 10.Rated power: less than 3W; 11.Sound level: ≧70db (within 1 meter). 12.Execute Criterion:GB15322;EN50291;UL2034; 13.Dimension:115*72*41mm. 14.sending frequency：315MHZ or 433MHZ，sending distance：100m(open area).