The Olfa L-5 X-Design is a high quality heavy-duty snap-off blade knife, ideal for craft or general purpose use. Designed in 1956 by Mr Y Okada, the Olfa is the original and widely-copied snap-off blade knife. In 1967, when most tools were black, Mr Okada decided that for safety reasons, his knives would be easily distinguishable in the toolbox - hence the bright yellow colour. Olfa blades are made from the finest quality tool steel, to ensure maximum life. The side lock wheel keeps the blade rigid, unlike cheaper versions which have a sprung button which can easily be depressed, thus releasing the blade.