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INSTALLED ONCE.
ADJUSTED IN SECONDS.
USED FOR YEARS.

The Retenser works with any tennis string, fits almost any modern racket, and is operated entirely by hand. Here's exactly how it works - from installation to your first adjustment on court.

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INSTALLED ONCE.
ADJUSTED IN SECONDS.
USED FOR YEARS.

The Retenser works with any tennis string, fits almost any modern racket, and is operated entirely by hand. Here's exactly how it works - from installation to your first adjustment on court.

HOW IT WORKS

Keep your tennis string longer tightened in a single, easy hand movement using the adjustable string tensioner that fits almost any modern tennis racket.

Step 1: Install at your next restring

The Retenser replaces the grommet strip at the bottom of your racket's bridge and is fitted during a standard restring. Any professional stringer can install it. If yours hasn't seen one before, simply show them the QR code in the box — the installation video is clear enough that they'll complete it first time without needing to call us.

Installation adds minimal time to the restring process. Choose the base part (flat or rounded) that best fits your racket's bridge shape, and your stringer threads your new strings straight through the Retenser cylinders. That's it — you're set up for the season.

Step 2: Start in the minus position

When your Retenser is first installed, set all cylinders to the Start (minus) position. This gives you two full tension adjustments in reserve — allowing you to increase tension as your strings naturally relax over the weeks ahead. Make sure all cylinders are in the same position; uneven settings create uneven tension across the string bed.

Step 3: Turn the key when you need it

Step 3: Turn the key when you need it
Step 3: Turn the key when you need it
Step 3: Turn the key when you need it

When your strings begin to feel loose or unresponsive, take out the adjustment key. Slide your finger through the safety cord, grip the cylinder, and rotate. One audible click moves all cylinders from Start to Middle — restoring up to 2 kg of lost tension instantly. You'll feel the difference before your next point.

When strings lose tension again, repeat: Middle to Plus. After two adjustments, your strings have had the full benefit of the Retenser — and it's time for a new set of strings (and to reinstall your Retenser for another season).

Step 4: Keep your Retenser for up to 10 uses

The Retenser is built to last. Made from high-strength materials engineered to withstand the forces of string tension repeatedly over time. When you restring, your stringer reinstalls the same Retenser. There's no replacement product to buy — just better strings for longer, season after season.

SCIENCE SECTION

WHAT TENSION LOSS ACTUALLY DOES TO YOUR GAME

Every tennis string starts losing tension the moment it leaves the stringing machine. Temperature, gameplay, storage conditions, and string type all affect the rate — but the direction is always the same: down.

Within a few weeks of use, a racket strung at 25 kg can feel more like 21 kg.

The effects are gradual and insidious. You swing harder to compensate. Your arm absorbs more shock. Your shots lose their depth and precision. You might not notice — until you pick up a freshly strung racket and realise how much you've been compensating.

The Retenser breaks this cycle entirely. Instead of accepting tension loss as inevitable, you correct it — on your schedule, on court, in seconds.

TENSION OVER TIME (EXAMPLE)

26 24 22 20 18
WEEKS
Without Retenser
With Retenser (adjusted)
group

Ready to take control of your string tension?

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