It is also used as a softwood timber in stair treads and joinery. It has steel stringers, timber treads and a steel balustrade. The steel treads sit on flat hard rubber tires. Stairway, treads, and walkways must be free of dangerous objects, debris and materials. Manufacturers now offer wading boots with special rubber treads or metal studs. A mono string staircase is a term used for a steel spine staircase with treads. The company manufactures rubber products including tyres, treads, tubes and conveyor belts, paints and toys. Ash stairs are extremely hard-wearing, which is particularly important for treads. Two sets are applied against the treads of the steel wheels for friction braking. Locomotive brakes employ large shoes which press against the driving wheel treads. The treads are often made from teak. Many variants have been created which use wheels or treads for locomotion. But it is a tricky tightrope which he treads with skill. The of concrete necessary for the treads was poured at the same time. Do not assail this divine Aeneid; nay, rather prostrate revere the ground that it treads.