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 a genuine OEM replacement kit.
This kit is threaded into the pump assembly.
It is connected to the Chemical Siphon Tube that is placed in a container that contains the cleaner you are using.
The O-Rings are placed on the Bronze nozzle, then the spring will go in first, then the steel ball, then thread in the nozzle.

This is an OEM part sourced directly from the manufacturer. Part is sold individually. Does not include the thermal relief valve (678169004) Commonly used in pressure washers, this pump creates a high volume pressure, supplying water through the high pressure hose, to the gun, and out through the pressure wand. This specific pump is only sold as a complete assembly.

This is a genuine Ryobi replacement high pressure hose that is supplied directly from original equipment manufacturer. It is specially designed for use with pressure washers. This high pressure hose is made out of rubber/plastic material. It is 25 ft long and it is sold individually. This hose can be used on pumps that produce up to 1700 PSI.

This is a genuine OEM part sourced from Ryobi for use in some of their electric pressure washers. This plastic trigger handle connects to spray wand and hose. If any of these parts are cracked, the machine won't work due to loss of pressure. Luckily this is a quick repair requiring no special tools; every connection is twist on/off. Use care to avoid over-tightening hose connection. This part is sold individually. Note that trigger handle warning labels are sold separately.

This replacement spray wand is specially made for use with Ryobi pressure washers. It is supplied directly from original manufacturer and it is sold individually. This items connects to the pistol/gun and allows user to connect nozzles to change spray patterns. This is a commonly replaced part due to regular wear, damage or if it is lost.

Replacing a wand is easy and does not require any tools.