CM927, CMS927, CMS927B1049. Adept Wireless Programmable Thermostat - Replaces Honeywell CMS927 & CMS921 Wireless Programmable Room Thermostats. CM921, CMS921, CMS921B1042. However, the big difference is that the Adept Wireless Programmable Thermostat will bind directly to an existing Honeywell BDR91 Wireless Relay Box (these are square not rectangular, see note below), whereas the T3 Series won't.
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