ST3 Tether System
The closest thing to open-water swimming in your own pool. 39 inches of progressive flex moves with your stroke — not against it.
- Free US shipping $99+
- 1-year warranty
- 30-day returns
Will the ST3 work in my pool?
Built for serious swim training. Here's the fit guide — verify before you order.
Works With
- In-ground pools 14 ft or longer
- Above-ground pools with a solid mounting surface
- Swim spas 14 ft+ (Endless, SwimEx, Master Spas, etc.)
- Concrete, wood deck, or paver mounts
Perfect For
- Lap swimmers who want the most natural, open-water feel
- Triathletes and distance swimmers maintaining race fitness
- Anyone with a pool 14 ft or longer
- Swimmers who've tried jets and wanted better stroke quality
Not sure your deck will work? Any flat surface at least 6–12" from the water's edge — concrete pad, wood deck, paver stone, or a PVC sleeve set in concrete — works with our concrete or threaded-wood base. Send us a photo if you'd like us to confirm fit before ordering.
Why the ST3
The Most Natural Stroke
Triple-rod fiberglass construction delivers 39 inches of smooth, progressive flex. The pole moves with you — no jarring stops, no feeling locked in place. Swim all four strokes naturally.
Train Like Open Water
Triathletes, distance swimmers, and coaches choose the ST3 because the resistance profile mimics real-world conditions. Build endurance and refine technique without leaving home.
Simple Setup. No Plumber.
Mount the base to your deck. Drop in the pole. Clip the cord to your belt. That's it. No electricity, no plumbing, no contractor. Works with any pool or swim spa.
How It Feels
Most tethered swimming systems fight your stroke. The ST3 doesn't. Three interlocking fiberglass rods create a progressive flex curve — light resistance at the start of your pull, building naturally as you extend. The result is a swimming rhythm that feels earned, not forced.
Freestyle, backstroke, breaststroke, butterfly — the ST3 handles all four strokes because the flex is long enough to follow your body's natural arc. That's why competitive swimmers and triathletes prefer it over shorter poles.
Built to Stay Outside
UV-resistant fiberglass won't fade, crack, or degrade in direct sunlight. 316 stainless steel fittings resist pool chemicals and saltwater. The Dynamic Stretch Cord is EPDM rubber rated for tens of thousands of cycles.
Leave it installed year-round. The ST3 is designed for the elements — not your garage.
What's In the Box
Every ST3 system ships complete: three-piece fiberglass pole, your choice of base, Dynamic Stretch Cord with carabiner, swim belt, and nylon carry bag. Concrete and threaded wood bases also include a rubber plug that caps the base when the pole isn't installed. Nothing else to buy — you're swimming the day it arrives.
Free shipping on orders over $99 in the continental US. International flat-rate shipping available.
What Swimmers Say
Also in the Swim Tether lineup
Every swimmer is different. Here are the other options.
Our most popular model. Two-piece design balances flex and stability — great for families and everyday fitness swimming.
View Details →Short, rigid, purpose-built for water aerobics, aqua jogging, and resistance training. The anchor that doesn't move.
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