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ERT300 Tennis String Tester

Unfortunately, the ERT300 is currently sold out. The next production will be available in April 2023.

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High tech measuring device for fully automatic measurement of stringbed stiffness and the playing characteristics on each tennis racket. The patented technology of world class players! Fast and precise! Swiss Made! Pay attention to the string because it is the engine of your racket.

 Stringbed stiffness - DYNAMIC TENSION DT - that is optimally adjusted to your playing style and level, you get the most out of the interaction between racket and string.

YOU DECIDE: Do I need tight or rather soft string tension for my game? Are the strings on my tournament rackets identical? When do my rackets need to be restrung?




-The ERT300 gives me confidence that my rackets are strung optimally and that my string is performing at its best. I can fully concentrate on the opponent and the game.


-A must for every stringer! With the ERT300 I can check the quality of my work at any time and advise my customers competently. I now know exactly when I need to renew his string and I can recreate its optimal DT value at any time with a new restring. Real quality work!


-The ERT300 is part of the professional equipment of a tennis coach. It helps my customers improve their game by determining the optimal DT value with them. I check their strings and advise them when they should change them.


-With the ERT300 I can optimize the advice I give to my customers as a tennis retailer. I know if they have the right string for their game, the optimal DT value and when the strings need to be replaced. I can give them what they need, making me their competent contact.

 " ...We have tested numerous measuring devices, only with the ERT 300 were we satisfied!"

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