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Fits exactly where it's supposed to and that underside pressure is something else. You can feel it working the moment you put it on, and it stays put without needing to adjust. Definitely a keeper for solo play.

Was a bit skeptical about sizing, but the steel ball fits snugly right under the head and stays put during use. The sensation is exactly what I hoped for, hitting that spot just above the shaft. Solid construction, no sharp edges, definitely worth the money.