Large plate size: 6.81x5in, Large plate inner size: 1.81x2.17in; Small plate size: 5.51x4.33in, Small plate inner size: 1.81x2.17in. 【Thermostat Backplate Compatible】: Cover plates are designed specifically for that thermostat, assembly work with all of the newer Honeywell thermostats such as (RTH9580WF, RTH9585WF1004, TH9320WF5003, RTH6570E、RTH95 85WF) and Prestige IAQ Thermostat.You can mount this cover plate directly to wall or a 2in x 4in electrical box, Use the THP2400A1027 cover plate assembly to cover marks on the wall.
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