Genuine OEM replacement part, this item is sold as one unit.
The purpose of the 309515003 Pump is to create water pressure to operate the Power Washers shown below.
There are are no internal parts available for this pump.
To remove the pump,remove the four screws securing the pump to the engine assembly.
You will be able to remove the pump at this time.

This is a genuine OEM sourced replacement part designed for use with Ridgid pressure washers. It is the essential part of the unit allowing to direct and control the spray. Please note the wand is sold separately. This pistol assembly is made out of plastic and metal. It is sold individually. Includes an ergonomic front soft rubber handle for better grip.

This is a genuine OEM approved replacement part designed for use with generators and pressure washers. The purpose of it is to filter out dirt and other debris from contaminating the carburetor. It will over time become clogged and restrict the fuel getting to the carburetor so it will need to be replaced. It is made out of plastic, it is sold individually.

This is a genuine OEM replacement part, this item is sold individually.
The purpose of the 678169004 Thermal Relief Valve is one of safety.
In the event that the water in the pump continues to circulate without being discharged, the Thermal Relief Valve will open and release the water and pressure from the the pump so it will not be damaged.

This is an OEM part sourced from the original manufacturer for use with pressure washers. This stainless steel spray wand screws into the trigger handle assembly, giving a 21" reach. One spray wand is included.