Golf In Sync ($90, birdietown.com) is an actual training aid from Sweden, not an information provider like Zepp. The Golf In Sync device straps on to your upper left arm (if you’re a righty) and there’s a rod that attaches to the shaft and slides along as you swing. The hookup forces you to stay connected through the whole swing, including through impact. It’s more awkward to explain than it is to use. It is somewhat similar to one me of my favorite all-time training device, the True Ympact (pronounced impact), a terrific aid for hitting pitch shots, although I’m not positive they’re still being produced. I like Golf In Sync more for longer pitch shots and short game stuff because it keeps you from manipulating the club with your hands and forces you to turn your body back and through and keep the club in front of your chest. It’s very good.