Helps to make the railing door comfortable and sturdy, ensuring the safety of children or pets. This pressure screw ensures safety and stability, making your baby door more stable and preventing any malfunctions. Rubber ends are a good way to protect walls or stair handrails from scratches. (Do not use at the top of stairs) Easy to install Our threaded spindle rod comes with adjustable length bolts, does not require tools, and does not drill holes in the wall. These spindle rods work like factory bolts. Simply rotate the nut to generate a reverse force on the wall for quick and easy installation. Widely applicable to all pressure doors, baby doors, pet doors, ultra wide and high doors, and child safety doors with doors. Suitable for all pressure installed baby or pet doors. Replace the 4-pack threaded valve stem to put the old door back into use, saving the trouble of purchasing a new door. The packaging includes 4 sets of threaded spindle rods. Size: Diameter M10 (10mm), length 80mm, top diameter 35mm (1.38 inches), only applicable to M10 spindle hole. Not applicable to 8mm screws. Color: White Features: 1. This type of door adapter is quick and easy to install, and does not require tools. Before purchasing, please ensure that your baby door hole can be inserted with M10 (10mm) bolts. Protect your walls, doors, stairs, and railings from damage caused by pressure doors or dog doors. The rubber end can protect the stairs from scratches, and a baby safety door can be installed on the stairs, leaning against the railing and round pole.