PX-603PC photoelectronic smoke detector（network） 9-16V D.C，Sound & flash alarm，anti white light interference; Alarm Output: relay output N.O./N.C,Alarm volume: more than 85dB/m. PX-603P photoelectronic smoke detector (independent) 9V battery，use in dependence，sound&flash alarm，test manually，auto reset, Alarm volume: more than 85dB/m PX-603PR wireless photoelectronic smoke detector 9V battery，Radia Frequency:315M or 433M， Radio distance：more than 100m(open area), Alarm volume: more than 85dB/m.