The digital cylinder is a universal-type, quickly installed door release element. A specially developed modular extension system makes it possible to extend both sides of the cylinder by up to 15 mm in 5 mm increments respectively. That means it is possible to create 76 different cylinder lengths with just 5 standard cylinder bodies. For installation purposes it is possible to remove the rotary knob on both sides from the shafts. The designed-in ability to totally dismantle this cylinder opens up new storage and service options. The mechanical side is fixed. Supplied without a reader unit the basic mechatronic body can be fitted with a variety of reader heads. These can be mounted either from the front (simple battery change) or from the rear (increased security). MIFARE DESFire or LEGIC advant technology are preferred when printable passive ID cards are used.