Karcher Pressure Washer Control Head v2 - 22mm 9002029 9.002-029.0 GENUINE
K4 MY KARCHER RU (1.637-359.0). K3 COMPACT AU (1.637-308.0). To find your model number - Pressure Washers should have a sticker with the information on. You should be able to find this on the base, or where the mains cord flows into the unit.