I purchased the Sebo K3 pet last year, and then recently moved into a house with a central vacuum system. I love the ET-1 power brush head and was disappointed that it didn't fit with the central vac hose. This converter is the perfect inexpensive solution and allows the ET-1 to be used with the central vac. This fits on to the end of the central vac wand (the end that attaches to the brush) & NOT the Sebo wand. The converter still allows the ET-1 to disattach from the central vac so the brush head can be used with both the central vac and the Sebo canister. Best of both worlds.