These models allow the open cover to rest lower against the spa for a slightly less-obstructed view. The CoverMate Understyle can be simply slid underneath for spas with weaker skirts using the Understyle bracket system. Requires just 18 inches clearance behind spa. Powdercoated, aluminum tubing with easy-to-install, non-corrosive mounting brackets. The Understyle system uses two aluminum brackets and 7-inch base plates that simply slide under the spa. Comes standard with a TowelMate accessory for hanging up to three towels right where you need them most. - 4 per case