Pressure test plug can be used to cap open ended pipes, pipe spools and piping systems and remove the need to fit flanges/ blind flanges which is the traditional way to hydro-statically test and eliminates the need for hot work and consequent permits. It's a fast-track, proven high pressure testing system for hydro-testing short or long span pipework or spools. And also, it's a fast-track proven system for hydro-testing in-situ valves or retro-fit valves. http://www.huancheng-valve.com/pressure-gauge-accessories/pressure-test-plug/