With higher quality and competitive price, Yuanheng DST tools occupy more than 70-80% of the domestic market .We are proud to be the qualified supplier of CNPC (China National Petroleum Corporation) SINOPEC CORP�China Petroleum and Chemical Corporation. CNOOC (China National Offshore Oil Corporation) etc. Nowadays, the good reputation of Yuanheng DST Tools begins to gain the great market in the oil-producing countries like Pakistan, Iran, Indonesia, Canada , etc. In the early 2000, our company gained the certificate of ISO9001:1994 from Chinese quality assurance center of authentication and we updated to ISO9001:2000 in 2003. In 2007, Yuanheng was certificated �high tech� enterprise. In 2012, Yuanheng got API audit and been certificated API License, API QMS ISO 9001:2008, ISO/TS 29001 and API specification Q1. Products Range: RTTS Packer RTTS Safety Joint FUL-FLO Hydraulic Circulating Valve Internal Pressure-Operated (IPO) Circulating Valve Repetitious Circulating Valve RTTS Circulating Valve Rupture Disk (RD) Safety Circulating Valve Tester Valve Select Tester Valve Tubing String Testing (TST) Valve Rupture Disk (RD) Tubing String Testing (TST) Valve Round Mandrel Slip joint Shock Absorber Hollow Plug Impact Reversing Sub HYDROSPRING Tester VR Safety Joint Champ Packer Bridge Plugs PRESSURE OPERATED Tester Valve(LPR-N) OMNI Valve Pressure gauge carrier MFE In order to diversify our existing market, we are interested in supplying our high quality products to you on favorable terms and conditions. Upon receipt of your inquiries. For more information, Please find our website at : ***** If you are interested in our products, please contact us at any time.