Metal joint-set KJ-1 to KJ-4 is universal connection way,from which we can design many products and then assemble them ,this four kinds is widly used when you designing new goods,if you remenber them ,you will work more easilly. King 9 has manufactured and saled metal joint for many years,We know what does customer need and how to make sure our products has high quality.At the same time we can service timely and accurate,King 9 has own product catalog and a direct sales marketing system,according to the recommenda-tions and requirements of the customers to make products and services.