[ADHESIVE MOUNT - NO DRILLING] Use the adhesive strip and stick the ceiling mount plate and magnetic mount to the smoke detector - if you choose to use ceiling screw mounts you may damage the cables. [QUICK ASSEMBLY - UNIVERSAL FOR ALL TYPES OF ALARMS] You can attach these magnetic smoke detector brackets without tools. The surface of your alarm device must be flat and have a diameter of at least 70 mm. [EXTRA STRONG ADHESIVE] 3M adhesive pads for smoke detectors and the 2 strong neodymium magnets can be used universally for fire alarms and carbon monoxide alarms. [EASY BATTERY CHANGE GUARANTEED] These magnetic mounting plates for alarms make function testing and battery changing super simple. [DELIVERY INCLUDED] 3 x Universal magnetic mount for smoke detectors.