The safety gate Stop N Safe 2 comes with a 21cm extension and can be used to childproof openings of 96 to 101 cm. If you want to secure smaller openings (84 - 89 cm), we recommend the Stop N Safe 2 that comes with a 9cm extension and for standard openings (75 - 80 cm) the Stop N Safe 2 without any extension. Each gate can be combined with a maximum of two extensions, one on each side. For round stair railings, we recommend our Y-spindle. The metal safety gate is installed with four fixing screws by pressure in between stairs, walls or doors and leaves no trace when removed. , , Adults can open the 50 cm wide door with one hand only in both directions. This way, one hand remains free for the little explorer. The door's two-fold manual locking mechanism can't be opened by small children. With an additional 9 cm or 21 cm extension (sold separately), the Stop N Safe 2 gate can be extended up to 122 cm. If the gate is to be installed on round stair railings, we recommend the hauck Y-Spindles as accessories. These replace the fixing screws on the safety gate's side that needs to be fixed on round railings. , , The following opening widths are possible: 75 - 80 cm = safety gate (without extensions)96 - 101 cm = safety gate + 21 cm extension (included)105 - 110 cm = safety gate + 21 cm extension (included) + 9 cm extension (optional)117 - 122 cm = safety gate + 21 cm extension (included) + 21 cm extension (optional) Please note: This item is a self-adjusting gate. This means that the initial inclination of the side part is eliminated by tightening the locking screws in the frame. This way, a secure hold and a parallel fixation of the side parts is possibile.