- Maximum Vertical Clearance: For optimal installation, maintain a vertical clearance of 0.25 inches (1/4 inch) to 1.5 inches between your door and the floor. This product is ideal for inswing doors with a 3mm clearance and includes a three-size spacer keyring set for precise fitting. - Easy Installation: No tools are needed for setup. Simply place the device beneath the door handle, slide it under the door, and twist the screw clockwise for a secure hold. In case of emergencies, the quick-release feature allows for instant removal by pulling upwards. - Versatile Compatibility: Designed to accommodate doors weighing up to 100lbs, this device is suitable for various door types, including interior, hotel, and travel doors. It securely anchors to surfaces such as tile, laminate, and carpet, ensuring reliable protection in any environment. - Lightweight and Compact: Weighing only 227g and measuring 4.5" x 3.5", this device is portable and easy to store. It includes a durable neoprene extension foot for enhanced grip on thicker carpets, making it perfect for both travelers and home use. Use Scenarios: 1. Secure your hotel door during your stay for added peace of mind. 2. Use it at home to keep interior doors safely locked when necessary. 3. Perfect for travelers who want an extra layer of security in unfamiliar environments.