How do catchers relay signals to pitchers? How does PitchCom work? - AS USA
Giants catchers, pitchers adjusting to fingerless signs with PitchCom
MLB approves use of electronic pitch calling - Chicago Sun-Times
Radio communication helping catchers get calls
College Baseball Was On the Clock and Chose an Electronic Wristband
Coach resigns after players caught with illegal devices in helmets
Baseball: One-way communication devices get green light for catchers, Sports
MLB gives OK to electronic pitch calling
Rays tuned in to new electronic pitch-calling technology
College baseball goes high-tech to send pitch calls to mound
Baseball NCAA NFHS Compliant One-Way Communication Device Coach to Player, Pitcher, Catcher — Qubit
PitchCom approved for use in 2022 regular season
Electronic communications devices from dugout to catcher to be permitted in high school baseball, High School
Baseball must embrace technology in pitcher-catcher communication