This funnel is a smart idea. Screw it into the opening and it does not move (unlike traditional funnels that often have to be held with one hand). Excellent design that makes oil changing easier.
Even though it's really not a big deal to hold a funnel, the threaded one ensures you will have no spills.
Works good with no wobble or mess. Handy service tool.
Worked great. Glad I purchased
Overall the funnel is good. I wish the mouth was a larger diameter as the 5 quart jugs are hard to handle and pouring is still tricky. A wider diameter would make it easier, but overall for one hand operation it's great.