... China. Our products fully passed ISO9001-2000 international quality system and 3C authentication. Moreover,pls be noted that:1, ... geometric location of each component through rigorous X-ray non- destructive testing and magnetic particle testing inspection. 3, seal on the product, ... testing various technical indicators. 4, A, B Class 100% ray weld inspection, II level qualified, C, D Class welds 100% ...