Cardboard Bending Stiffness Tester Product Introduction Stiffness tester is a multi-functional intelligent computerized stiffness tester, suitable for measuring the bending stiffness of paper, cardboard and other non-metallic materials with a thickness of less than 2mm. The test angle of the instrument can be set arbitrarily between (1~90)°, and the test time can be set arbitrarily within the specified range (3s~30s). With automatic zero test function, it is the first