The GEZE Boxer integrated door closer for single-leaf doors is incorporated discreetly into the door leaf and frame. The guide rail and lever are only visible when the door is open. Once the door is installed, the closing force and speed, latching action and hydraulic back check can be conveniently adjusted from the top. The door closer can be used for right and left single-action doors without any need for conversion. An additional door suitability certificate is required for fireproof doors. The door must be limited at an opening angle of about 120°.