Manufacturer: Tyco Fire and Security GmbH "Fire Alarm System - Smoke Sensors

Optical smoke and heat detector 851PH, EN54-5 P, EN54-7, 

EN54-17:2005, VDS2806 CEA4021, Uses :MX Digital 

Protocol" TYCO.851PH.516.850.055

Manufacturer: Tyco Fire and Security GmbH "Fire Alarm System - Isolator Base

* 5BI 5"" Isolator Base for Optical smoke and heat detector 851PH,  0786-CPD-20762" TYCO.851PH.517.050.018