This latest dual-string interlocking shear and seal ram was developed in response to evolving regulations in the Gulf of Mexico (BSEE 30 CFR Part 250.733[a][1]). Its more efficient cutting geometry requires 40% lower shearing force than previous interlocking shear rams while shearing everything from zero-tension wireline to dual strings and heavy drillpipe. The new seal geometry and design provide full wellbore coverage and enable the ram to seal under extreme heat. The DSI rams were tested in conjunction with a major Middle East operator to 350 degF [176.7 degC] with an 8-h hold—simulating conditions seen in the Middle East's most challenging wells.