Euro Cylinder and Turn. To lock the door on the inside, simply use the turn knob, there's no need for a key. Overall length, external and internal dimensions are; 70mm (35/35mm). These MP5 Architectural 5 pin cylinders provide a good degree of security. Certified to British/European standards( BS EN 1303) and fire door rated. Keyed alike or master keyed options available. Comes with a 5 year mechanical guarantee. Suitable for domestic and commercial use.