GSI Industries specializes in providing a wide range of tools and equipment for fuel pressure testing, pressure testing for oil, transmission, tires, brakes, power steering, and exhaust systems, as well as diesel tools including compression testing, fuel cleaning, and fuel pressure testing. Their products include fuel pressure test kits, basic fuel injection test sets, brake pressure sets, power steering sets, diesel compression test sets, diesel cleaning canisters, and more. GSI Industries offers a variety of adapters and gauges to check pressures and diagnose issues in automotive systems. They also provide information on their website about delivery, returns, and customer service.