Need a reliable smoke detector for your home or business? This is the SECUTRON MRI-2251B, an intelligent photoelectronic smoke detector. It's brand new, in its original packaging, ready to install. Photoelectric detectors are great at sensing slow, smoldering fires (like from a cigarette in a couch) faster than the other main type. The 'intelligent' part likely means it can communicate with a central alarm system or other detectors. The model is MRI-2251B (also listed as MRI2251B, etc.). SECUTRON is a known brand in the commercial and residential safety market. Whether you're replacing an old unit, adding coverage, or installing a new system, this is a quality, professional-grade detector. Safety first! Always follow local building codes for installation and placement. Keep your family or property protected with this essential device.