What should be paid attention to when using magnets? 1) Only iron materials can be absorbed, metals without iron cannot be absorbed. 2) Magnets are fragile items made by sintering neodymium iron boron powder, which is hard and brittle, so fragility is not a quality issue; Strong magnetism, be careful not to pinch your hands, store in a dry environment at room temperature. 3) The unit of magnet size is millimeters (mm), and all products have certain tolerances: ± 0.5 (size 10mm), ± 1 (10<size ≤ 30mm), ± 2 (size>30mm). Our store does not accept complaints within the tolerance range. Please be cautious when placing orders if you mind. 4) Do not put electronic products such as mobile phones and watches together to avoid strong magnetic interference