A glass knife is mainly used for cutting large glass and window panes. Splitting glass is easy when you have the right tools. In order to break the glass straight at the right point, you need to make a cut with a glass knife. Press the knife firmly against the glass, using a ruler as an aid, and make a cut in the glass. The glass can be split along the cut by pressing it down on both sides of the cut. High-quality glass knifeBlade options: 2, 3, 4, 5 and 6 mm