EPDM Rubber U-Boat Floor Floaters (otherwise known as Damping Shoes or C-Channel Suspension Isolators) support and acoustically isolate floor framing members, i.e joists, to lessen the sound waves passing from one side of the structure to the other. The U-Boats are extruded from EPDM Rubber that is formulated to reduce or eliminate vibrations. Dimensions / Specifics: U-Boats are shaped to accommodate standard joist dimensions, and molded to fit around the edge of any 2 by X joist. Width: 1.5” (38.1mm) Height: 2.125” (54.0mm) Length: 2” (50.08mm) Thickness: Sides- .313” (7.9mm); Base- .5” (12.7mm) Color: Black High Quality: Made in the HSA What is EPDM? EPDM Rubber (Ethylene-Propylene-Diene-Monomer) is comparable to Neoprene Rubber, however it surpasses it in performance and is a more eco-friendly option. Specifically, it has outstanding resistance to abrasion, hydraulic fluids, alkalis, heat, ozone, and weather. How Many Do I Need? If Joist Spacing is 24” OC, U Boats should be installed at a minimum of 16” OC along the joist and should not exceed 24” OC. If Joist Spacing is between 12” and 16” OC, U Boats should be installed at a minimum of 16” OC along the joist and should not exceed 32” OC. TIP: If Joist Spacing is 16” OC with U Boats installed at 16” OC on joist, multiply the total square footage of your room by 2/3 to calculate approximate U Boats needed.