The tilted shelves of the XM-4439 ensure easy loading and unloading of dumbbells. Measuring 1 3/4″ the back shelf lift holds larger dumbbells in place, while the shelves provide ample space between dumbbells. Your flooring is protected from scratches with the rubber feet which are skid resistant. The heavy duty construction of the XM-4439 perfectly accommodates a 550 lb. set of dumbbells. Dumbbells are NOT included with this rack.