15mm diameter x 2mm thick. 4.2mm diameter countersunk hole. Can be fixed in place using an M4 countersunk screw. These steel discs are the perfect solution for installing a magnetic surface that magnets will stick to. For example, you could screw one of these discs into a wall and then, using magnets, hang artwork or noticeboards. Each disc can be fixed in place using an M4 countersunk screw.
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