One box has it all. This connection kit has been designed to make installation and maintenance so much easier for your tankless water heater. The kit contains 1 set of 3/4 in. FIP service valves, pressure relief valve, coated gas connector (290,900 BTU) and stainless steel water heater connectors. 100% leak-tested for safety. Lead free for potable water application. Please see the specification sheet for more details.