The four-point bending clamp is suitable for four-point bending testing of plastics, metals, ceramics, pipes and other materials. The clamp has two base sizes and different pressure roller diameters; two bases are used in the 4-point bending test. The device complies with ASTMO393, C1161, D790 and related standards. The base has multiple V-shaped grooves, which can place pressure rollers of different diameters, and pressure rollers of different sizes can be selected for testing according to the test. There is a double-scale scale on the green side of the base, with an inch scale on one side and a meter scale on the other side. The universal mounting holes require an optional quick-connect adapter and can be fixedly installed with the tension and compression sensor or measuring table of the universal testing machine.