YOUR STRINGS LOSE TENSION WITH EVERY HIT OF THE TENNIS BALL.
EVERY TENNIS PLAYER HAS THIS PROBLEM.
Most don't know it yet.
The moment your strings leave the stringing machine, they begin losing tension. Not just when you play — during storage, in changing temperatures, even overnight. Within weeks, that perfectly-set 25 kg feels like 22 kg. You work harder for less power. Your control slips. Your arm takes the strain. You book another restring — and the cycle starts again.
There is a smarter way.
PLAY YOUR BEST FOR LONGER
Restore the snap, power and precision of freshly strung strings — in 10 seconds, before you even walk on court.
CUT YOUR RESTRINGING COSTS
The Retenser extends string life across an entire season. It pays for itself from the very first restring you don't need to book.
ADAPT TO ANY CONDITION
Fast surface? Raise tension for control. Clay court or cold morning? Lower it for more power. Your racket, your tension, your call.
There is a smarter way.
— A Smarter Investment for Every Racquet.
One Retenser. Up to 10 Re-stringings.
INSTALL AT YOUR NEXT RESTRING
Your stringer fits the Retenser to the bridge of your racket in minutes.
Turn the key when you need it
When strings feel soft, use the included key to rotate the cylinders. One click = instantly restored tension. You'll feel it immediately.
Two adjustments per string set
Start → Middle → Plus. Two full tension boosts before your strings need replacing. Reuse the Retenser with every new string job.
TRUSTED BY PROFESSIONALS. LOVED BY CLUB PLAYERS WORLDWIDE.
“The retenser really helped me improve my game. During matches I can adjust the string tension either making my shots more impactful or help me playing better defensively. I recommend the retenser to any player who wants to improve their game and get more out of their strings.”
— Auke Jan
"Tennis Player, Dutch level 4"
“I’ve used the Retenser on my Yonex Ezone 98 for a few months, and it’s a lifesaver if you don't break strings quickly. Instead of restringing every few weeks, a couple of quick turns with the key easily restores lost tension and control. It’s a practical, highly recommended tool to extend your string lifespan and maintain peak performance without the hassle.”
— Mike
"Former international future tennis player"
“I am passionate about tennis. I started playing when I was 7 and am still playing at 71. The Retenser has given me a level of control over string tension that I have never experienced before. Even after the strings start to lose tension, I don't have to restring them. I can easily increase the tension with the 'magic' key. So thank you, Sander, for inventing the Retenser! So simple and so effective!”
— James Caldwell
"Tennis Player"
“When restringing my racket recently, I also bought a Retenser. A while later, tightening the strings was incredibly easy with just a simple turn. It instantly felt like a fresh restringing, allowing me to get the most out of my strings without needing an interim string job. Easy to use, instant results, and a minimal investment—a must-have for every tennis player!”
— Annelien
"Tennis Player"
“As both a tennis player and a physical therapist, I highly value the Retenser. Proper string tension is crucial, and this tool allows for subtle adjustments that heavily impact your technique. Constantly optimizing your tension based on temperature, daily form, or match play keeps you connected to your game, boosts performance, and reduces injury risk. It’s an essential piece of gear for any serious player.”
— Niels van der Meulen
"Physiotherapist & Master Manual Therapist"
“The Retenser is a special invention helping to fine tune a players game at the recreational level and up. Personally, I have seen obvious results using the Retenser in my racket as a player as well as a coach. The longevity of the string is amazing and worth buying this product for this reason alone!”
— Raoul
"Former College D1 athlete and 25+ year tennis coach"
CHOOSE YOUR RETENSER
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ITF Approved
Ready to play at your best — every single session?
The Retenser Standard starts at €34.95. Fits almost any modern racket. Reusable for up to 10 uses. Backed by a Red Dot Award, ITF approval, and players from ATP level to first-season club.
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