Smoke and Carbon Monoxide Alarm, Battery Chemistry Alkaline, Battery Location Side, Battery Locking Pin Yes, Battery Size 9V, Communication Protocol Hardwired Interconnect, Compatible With 1039102, 3120B, 7010, 7010B, 7010BSL, 7020B, 7020BSL, 7030BSL, 9120, 9120B, CO5120BN, CO5120PDBN, HD6135FB, RM4, SA520, SC7010B, SC7010BV, SC9120B, SLED177, SM100V-AC, SM110LED-AC, SM300-AC, SM500-AC, SMCO100V-AC, SMCO110LED-AC, SMI100-AC, SMI105-AC, SMICO100-AC, SMICO105-AC, Detector Type Smoke/CO Detector
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