Note:This magnet is a rubber magnet, not a metal magnet. DO NOT USE ON HEAVY THINGS LIKE FORKS, SPOON, etc.Please clean and keep dry of the surface you will apply before installing.The product is the rubber weak magnetism. The thickness, the apply area, and the surface flatness will decide the magnetism. Application:Great for shelf labeling and other small applications. Perfect for craft die storage, science education, classroom project, or applying adhesive items etc..Feature:REUSABLE magnetic stickers. Write on them with a dry erase marker, wipe them off and use them again.So easy to use and cut! You can decide what length you need.Black magnet on front and Green on back - NO ADHESIVE, magnetic on black side.Specifications:Overall Size: 297 x 210 x 0.