If you have that funky looking male plug on the end of your Karcher pressure washer, this is the adapter that you need to to convert it to accept a gun/wand package.
Here is what you need to make a gun like a Mosmatic or MTM work.
1.) Twist and Seal M22 to 3/8" Plug
2.) Female Stainless 3/8" Coupler
3.) Male Stainless 3/8" Plug
Note: None of the quick disconnects shown in the photos are included. They are sold separately.