Problem with that thing is you have to drop your elbow to keep the cue level and avoid hitting the top/bottom. I'd rather use something like two golf tees stood on end with a small space between so the tip can move up and down freely (and it's easy to tell when you hit a tee).I ordered this device from Seyberts and it should help me with my stroke accuracy, and hopefully acceleration. I think acceleration is something you want to keep consistent and smooth.
Buddy Hall Cue Guide
Improve your stroke by developing muscle memory. This simple aid will help you keep your stroke straight, your arm and cue working as one unit. The rotating rear foot gives you four different angles to practice your stroke. Use the Cue Guide in the privacy of your own home on a pool table, or...www.muellers.com
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