Panels are 2 1/2" thick with metal interior frames dividing each panel into 20 sub-compartments. Each sub compartment is filled with sound deadening materials. Panels are encased in thick fiberglass and UV protective gel coat unitized under pressure in large molds. Front and edges of panels are sprayed with a high quality impact, solar and temperature resistant green polyurethane Imron paint. Panel faces have no holes; attachment is in back with wheels. Wheels allow panels to roll in galvanized metal channels horizontally attached to fence post. Each panel weighs 150 lbs. Flat backboards are traditional; this is Bakko's oldest model and over the years, a best seller. Typically purchased by country clubs, resorts and private court owners. Most common purchased size is 5 panels. Call for shipping quote. Several other sizes available.