Blitzball teamed up with Gopher Sport to create the official Blitzball StrikeOut Strike Zone Indicator. This indicator ensures all players know the strike zone and eliminates the need for an umpire. Made of durable Magnus ABS tubing with a 31"L x 21-1/2"W vinyl mat indicating the strike zone. When the ball hits the indicator, it makes an easy-to-hear sound and drops to the ground fore easy collection. Secure the mat to the frame use Velcro® straps.