The purpose of the test is to define the responsibilities of garment manufacturers to ensure that buttons, buttons and fixtures are properly fastened to the garments, preventing buttons from escaping from the garment and creating a risk of ingestion by infants. Therefore, all buttons, buttons and fasteners on garments must be tested by a button strength tester. The machine can do uniform vertical tension test on all kinds of buttons to determine whether the fastness can meet the relevant safety standards. Standard: 16 CFR 1500.51-53, ASTM PS79-96