Similar cut to the TH17, the JM21 Custom Pro Model also offers a small barrel with a traditional knob, but a slightly larger handle than the TH17.
Marucci’s Smart Bat technology allows Diamond Kinetics’ SwingTracker sensor to be securely fitted inside of the actual knob of a Custom Pro Model bat. By selecting Smart-Ready knob, you’re authorizing Marucci’s wood production team to carve out part of the knob and install a dual-locking mechanism to firmly hold your SwingTracker sensor in place, allowing for the most accurate data possible.
The Diamond Kinetics SwingTracker sensor captures your most precise swing data using 11 different metrics in four core swing categories: speed, power, quickness, and control, then sends it to the SwingTracker app through a paired iOS device via Bluetooth. View metrics in easy-to-read graphics and charts or sync with a unique 3D image or video of your swing.