Honeywell RTH8500 Installation Manual page 11

Mount wallplate About your new thermostat
1. Drill holes at pencil-marked locations:
3/16" holes for drywall
7/32" holes for plaster.
2. Use hammer to tap
anchors into holes until
flush with wall.
3. Place wallplate over
anchors and insert screws.
Check level if desired,
then tighten screws.

RTH8500