Clear Plastic Thermostat Guard - See Thru - Solid Base - 8.25" x 5.37" - Extra Large - With Lock & Key w32h32 + Product Details Size -

+ Product Details Size - 10"w X 28"h is the size for the duct opening measurement only

+ Product Details Size - 30"w X 28"h is the size for the duct opening measurement only

so you are not left with much waste

actual front end outer dimensions are approximately 30 5/8" width X 34 5/8" height

Clear Plastic Thermostat Guard - See Thru - Solid Base - 8.25" x 5.37" - Extra Large - With Lock & Key w32h32 + Product Details Size -+ Product Details Universal Fit Accommodates almost any thermostat with dimensions of 8 1 4" H x 5 3 8" W x 3 1 2" D. Durable Construction Made from high quality, high impact clear plastic for long lasting performance. Locking Security System Features a built in eight tumbler lock and a supplied key to prevent tampering and maintain consistent temperature settings. Easy Installation Comes with all necessary installation screws for a quick and hassle