Fletcher-Terry 4" Professional Quality Glass Cutter with Hardened Tool Steel Cutting Wheel is designed for cutting single or double strength glass. It features a 130-degree cutting angle for easier scoring, built-in break-out notches, and a tapping ball. Cast from superior grade steel, this glass cutter has a classic contoured comfort grip handle in a straight or ball end style. The cutting wheel comes in a variety of angles for cutting all types of glass.