Magnetic sheet 200x300mm. It is possible to write on the sheet with whiteboardmarkers (non-permanent). Magnetic strength app. 35 g per square centimeter.
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Super product for storage shelves. If you need a cheap and easy way of marking your storage, then the magnetic ribbon is an option. Write the number directly on the ribbon or add a sticker - it can not be any easier.
Super product for storage shelves or planning boards. Sticks to any steel or metal surface.