Dock Edge Howell 550 Dock Float. The convenient design of the Howell 550 makes assembling your dock much easier! This rugged float is made from rotationally molded black virgin polyethylene with a consistent 5/16" wall thickness and 1/2" at fastening points for extremely strong resistance to splits and punctures. Recessed flanges and center trough allow float to be used on 2' or 4' centers. Each float has 10 easy to get at locations from which to attach the stringers. Recessed corners allow the float to be positioned tight into the corners for maximum stability. 24" x 48" x 16"H with 550 lb. flotation capacity. Backed by a 10-year warranty against defects.