The spin is in: What's up with the spin rate in baseball? - Bleed Cubbie Blue
Spin rate down, Cole struggles with grip on windy night | Baseball | lacrossetribune.com
Amazon.com : STRIKE Smart Baseball Training Equipment for Practice, Analysis Speed/Spin Rate/Pop Time Sensor, Official Size, Weight and Genuine Leather Skin as MLB (iOS/Android)(Smart Baseball) : Sports & Outdoors
M.L.B. Will Analyze Spin Rate to Detect Ball Doctoring - The New York Times