With the ERT 300 Tenniscomputer, you'll know when it's time to restring your racquet. The display shows current string bed stiffness (dynamic tension), indicating the power and aggressiveness of play and alerts when it is time to restring. Provides highly precise measurement through an electronic simulation of the ball impact. Pocket-sized, cordless, and easy to use. Works with any racquet and string type. Battery operated.

• Approx. 110 x 50 x 25mm
• Instruction manual and reference card included
• Batteries included