Just be sure it is for your units, heat and a/c types with same number of wires as minimum.
It will have to be battery operated or you will need to run a common wire from transformer to t-stat C connection.
I would get a Honeywell or White Rodgers and would buy from HVAC supply if possible. Better t-stats and knowledgeable help to get correct t-stat.
Take care and best wishes,
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