▲ This hardness gauge conforms to the regulations of GB/T531,GB2411, HG/T2489, JB6148. ▲ When using single pointer models, one should place the sample in the solid plane, hold the hardness gauge, keep the pressure needle at a distance of at least 12 mm from the edge of the sample, smooth enough pressure in the pressure on the sample, and smoothly press on the sample to a full extent.
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