I don't have a problem with design changes, that is normal. But, do not sell parts that are known have changed without stating so. New Horizon parts page simply states Eko Model 25. It gives no hint that it may not fit or that the design has changed. The alteration required was difficult and time consuming. If you buy an oil filter for your car, you expect it to fit. You should not have to spend time and effort modifying it to make it work.