No glue is needed when you have these super-strong Master Magnetics Disc Magnets with Adhesive. Just peel off the adhesive liner and stick it to your craft or project. Industrial-strength acrylic foam adhesive conforms to the irregularities of rigid substrates and adheres the magnet to a multitude of materials. The neodymium magnets attach to the back of objects that need a super-strong pull force. Use these silver magnets for practically any light, medium, or heavy-duty project, where super strong pull force is required. These neodymium disc magnets can be used to adhere to materials including wood, plastic, ceramic, rock, paper, and much more.