RPM Mats make the installation of floor heating cable fast and easy when using self leveling mortar. RPM Mats are 20” x 44” and Made in the USA from Heavy Duty 60 mil ABS plastic (80%+ recycled materials) but weigh only 2.0 lbs. This 1/2" thickness is usually chosen to increase floor height to meet an adjoining floor that is thicker. RPM has been used to install thousands of WarmWire® projects providing a lightweight, quick and clean option to a traditional backer board and cable guide strap installation. Simply thread the floor heating cable of your choice (not included) onto the grid between the studs at your desired spacing and it sits safely and securely 1/8” below the top of the studs so your installation is protected from traffic and tools. Once filled with cement leveling mortar your floor has a Lab tested and approved “heavy” rating. It is lighter then backerboard and installs in half the steps! On concrete slabs, it’s rated “High Performance” as an anti-fracture membrane in testing. Studs are ½” in diameter and spaced at 1”.