As a major manufacturer of valve cores,Youngbo continues to meet customer demand for quality and safety. Youngbo industrial company was founded in1976. We have produced many kinds of positive valve cores-for tire, air conditioner, and LP gas cylinder. We currently have two manufacturing plants, one in Korea and the other in China. This allows us to produce 36 million pcs of various valve cores per month. We export our products to Europe, Africa, South East Asia, China, Taiwan and U.S.A. We always do our best to supply our product with "reliable and perfect quality" to our customers. We have automatic gas leak testing machines. We ship out gas leak tested valve cores only to our customers.