1. Various sizes, adapt to different use environment, provide you with more choices. 2. Adequate-net weight, no cutting comers. 3. Except for standard weight, other optional weight series are available. Heavy and light. 4. Strict standards. By the ruler calibration. International testing standards. 5. Hardness <180. Fine workmanship 100%. 6. These fittings are widely connected to the pipes with water, oil, air, coal gas etc. as media.