Cast iron square box material: high quality gray cast iron HT200-250, according to JB/T3411.56-99 standards. Cast iron square box After two artificial annealing treatment, complete removal of internal stress, casting structural stability, not deformed. Cast iron square box Technical requirements: face can not have a serious impact on the appearance and performance of the sand holes, pores, cracks, slag, shrinkage, scratches, bumps, rust spots and other defects, otherwise it would be inaccurate measurements. Cast iron square box test uses: as an industrial production workshop fitter to do three-dimensional scribing tools; mechanical parts can also detect parallelism and verticality; also do bench use. Above with a bracket for precision parts inspection or draw lines at any angle. Engraved marker suitable for measuring and fixer. Cast iron square box material: high quality gray cast iron HT200-250, according to JB/T3411.56-99 standards. Cast iron square box after two manual annealing treatment, complete removal of internal stress, casting structural stability, not deformed. Cast iron square box test specifications: Can be customized according to user needs, our company can provide design drawings. Production cycle of 20 days