A portable ball machine, adjustable enough for use by beginners to professional tennis players. Variable ball speeds from 10 - 85 MPH. Variable ball feed from 1 1/2 - 12 seconds between balls. Adjustable trajectory from ground strokes to towering lobs. Repeat shots you need practice on or set the Tennis Tutor to deliver shots randomly across the entire court. Anti-jam ball feeding mechanism. Built-in battery with charger. Built-in handle allows the Tennis Tutor to be towed just like luggage. Holds 150 balls. Made in the USA. Has playtime of 4-6 hrs and includes a remote control!