Universal compatibility?Compatible with all types of flooring,the innovative system of hinges and angles anchor the door stopper firmly to carpeted, tiled and laminate floors when outside pressure is exerted on the door.fully adjustable extension foot corresponding to the gap.NOTE?The best use door gap size is 0.19?-1.18?. Carry-on protection?Whether you're at home, at the office, at school or on vacation.you can carry this product with you.very light but hard material can protect your safety. The hardest material:After years of research, we have produced this product. Small but very hard material. Don't worry about your safety, it can firmly hold the door.In case of emergency, you can easily remove the DoorJammer with an upward motion. Easy to use?Whether you are an adult or a child,you can use it easily.position the Door Blocker with the bottom flange under the door, directly below the door handle.adjust the foot so the Door Stopper is tightly fitted. Test the door, to make sure the Door Stopper is securely positioned.