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The ERT300 tennis computer is a microprocessor-controlled measuring device and determines the string and playing characteristics of your tennis racket precisely and quickly.

This makes the technology of world-class players accessible to every dedicated tennis player, stringer and coach - all in a small cell phone format.

The patented electronic measuring system has proven itself thousands of times and is the international reference! From now on, the new and improved ERT300 is available again! Now you can concentrate on your game - the string question is solved in seconds!


Are you still wondering what's wrong with your stringing?

With the ERT 300 you finally get the security of knowing instead of guessing. The string is the engine of your racket!

Who wants to have race car with the engine of a small car? Measure your string tension - Dynamic Tension DT- in a few seconds and get a precise result.

Only with a string tension that is optimally matched to your playing style and strength will you get the best out of your equipment!

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