These deterrents are designed to be used on metal or wood handrails and benches. They are the standard 1” GrinderMinder stainless steel ball, black oxide finished, with a threaded hole on the underside that will accept a bolt. Customer will drill a hole through the rail or bench surface and bolt these pieces on from the underside. Bolts are sold separately to the customer’s specified length. Other materials and finishes can be used for custom pieces.