Water-resistant & lightweight
AirLoc™ panels have no foam core to soak up water, so the cover weighs the same out of the box and years later: 35–40 lb, depending on size.
Learn about water resistance
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Spa Fitter
The Sundance Spas Hartford 680 takes the AIRCAP 1™ Medium — a foam-free replacement hot tub cover for square spas 86"–88". The Hartford 680's cabinet measures 88" x 88", inside the Medium's range. The cover weighs 35–40 lb for life, costs $1,195, is engineered to comply with ASTM F1346-23, and carries a 3-year limited warranty.

Your size: AIRCAP 1 Medium
Cabinet 88" x 88" fits 86"–88"
AIRCAP 1™ is a foam-free hot tub cover: rigid AirLoc™ air panels with no foam core to waterlog, a light 35–40 lb.
$1,195 with free shipping, usually at your front door within 3–5 business days.
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3-year limited warranty · In 100+ hot tub showrooms

Fit at a glance
| Spa cabinet | 88" x 88" |
|---|---|
| AIRCAP 1™ size | Medium fits 86"–88" |
| Cover weight | 35–40 lb — constant for life |
| Price | $1,195, free US shipping |
| Skirt | ZipTech™ modular, three lengths included |
| Safety | Engineered to comply with ASTM F1346-23 |
| Warranty | 3-year limited warranty |
Measure straight across the top of your spa, edge to edge, both ways, in inches.

Watch it open and close on a cover lifter
The AIRCAP 1™ comes in six sizes covering square spas from 77" to 94". Each size is built to overhang its band slightly — that is how a spa cover is meant to sit — so the Medium, which fits cabinets 86"–88", covers the Hartford 680's 88" x 88" shell with the right overhang.
At 88" the Hartford 680 is at the top of the Medium's 86"–88" range — the largest cabinet this size covers. Measure before ordering: half an inch more and the cover you need is the Large. Within Sundance Spas, the Hartford 680 shares that 88" x 88" cabinet with Chelsee 780 (2012 and earlier), Constance Select and Victoria Select — same footprint, same cover. The 23 Sundance Spas models we fit sit on 6 footprints, and the Hartford 680 is on number 4 of 6 from the smallest; together they span 6 of the six AIRCAP 1 sizes.
Cabinet dimensions can change between model years. Before ordering, measure your Hartford 680 at its widest point across the top, in both directions, including any acrylic lip that overhangs the cabinet — the SureFit™ guide walks through it in two measurements. If a figure you have found elsewhere is larger than ours, an overhanging lip is the usual reason. If your spa measures between two sizes, round up.
Every spa in our catalogue that measures 88" x 88" is on one page: hot tubs that take an 88" × 88" cover — the same AIRCAP 1™ Medium, at the same price.
Instead of a rigid foam core wrapped in vinyl, the AIRCAP 1™ uses welded drop-stitch construction: a sealed air chamber with no foam to absorb water, so it does not become the waterlogged two-person lift that ends most foam covers. More on how it insulates, how it holds up, and why it is foam-free — or estimate what your current foam cover weighs.
What customers are saying
Awesome product, my kids don’t complain about the cover anymore…
Best $$ I ever spent!
What this company has created in terms of an original and revolutionary product is nothing short of amazing.
For a reasonable price, I can cover my spa with a top that won’t get musty.
Nice and lightweight
…set up was super easy and took about 15 min total.
Installation was a breeze and we love it already!
Great customer service still matters, and frankly, not enough companies deliver it anymore. This company does, and that deserves recognition.
Do not wait to buy one.
Thoughtfully engineered
Three practical reasons to rethink your next hot tub cover.
AirLoc™ panels have no foam core to soak up water, so the cover weighs the same out of the box and years later: 35–40 lb, depending on size.
Learn about water resistanceThe sealed AirLoc™ air core has nothing in it to absorb water, so its insulation stays consistent for the life of the cover.
See how AIRCAP insulatesThree ZipTech™ skirt lengths come in the box, and a worn or damaged skirt can be replaced on its own, without replacing the whole cover.
See how ZipTech worksEvery detail matters
Fits or we make it right. Wrong size or changed your mind? Swap it or return it within 30 days of delivery. We send a prepaid return label and there’s no restocking fee. Covers must come back in like-new condition with all parts. Bought from an authorized retailer? That retailer’s return policy applies.
How the fit guarantee worksBacked by a three-year limited warranty against manufacturing defects.
Warranty detailsUse Spa Fitter™ or SureFit™, or contact us before you order and we will confirm your size.
Get fit helpNeed help? Contact thrml. to confirm your fit before you order.
The Sundance Spas Hartford 680 takes the AIRCAP 1 Medium, which fits square hot tubs measuring 86"–88" across. The Hartford 680's cabinet measures 88" x 88", inside that band. Measure your spa side to side across the top of the cabinet to confirm before ordering.
Yes — the Hartford 680's 88" x 88" square cabinet falls in the AIRCAP 1 Medium's 86"–88" range, and the ZipTech modular skirt system ships with three skirt lengths so the drop over the cabinet adjusts without a custom order. Cabinet sizes can change between model years, so confirm with two quick measurements.
The AIRCAP 1 costs $1,195 in every size, including the pump, three ZipTech skirt lengths, and tie-down straps, with free US shipping and 30-day returns. Unlike a foam cover it has no foam core to waterlog, so it stays at its original 35–40 lb weight for life.
The AIRCAP 1 Medium weighs 35–40 lb and keeps that weight permanently — its sealed drop-stitch air core cannot absorb water. A foam cover starts at 40–75 lb and gains weight as the foam saturates.
Showing the 4 Sundance Spas models that take the AIRCAP 1 Medium.
| Model | Cabinet | AIRCAP 1™ |
|---|---|---|
| AIRCAP 1™ XX-Small · fits 77"–79" | ||
| Berkeley | 78" x 78" | XX-Small |
| Brook | 78" x 78" | XX-Small |
| AIRCAP 1™ X-Small · fits 80"–82" | ||
| Prado 680 (2023 and later) | 80" x 80" | X-Small |
| AIRCAP 1™ Small · fits 83"–85" | ||
| Altamar 880 (2024 and later) | 84" x 84" | Small |
| Bristol 780 | 84" x 84" | Small |
| Edison 680 | 84" x 84" | Small |
| Hanover 780 | 84" x 84" | Small |
| Peyton 680 | 84" x 84" | Small |
| Vistamar 880 | 84" x 84" | Small |
| AIRCAP 1™ Medium · fits 86"–88" | ||
| Chelsee 780 (2012 and earlier) | 88" x 88" | Medium same cover as the Hartford 680 |
| Constance Select | 88" x 88" | Medium same cover as the Hartford 680 |
| Hartford 680 (this page) | 88" x 88" | Medium |
| Victoria Select | 88" x 88" | Medium same cover as the Hartford 680 |
| AIRCAP 1™ Large · fits 89"–91" | ||
| Cameo 880 | 89" x 89" | Large |
| Chelsee 780 (2013 and later) | 89" x 89" | Large |
| Hamilton 780 (2013 and later) | 89" x 89" | Large |
| Lisbon 980 | 89" x 89" | Large |
| McKinley 680 | 89" x 89" | Large |
| Odessa 980 | 89" x 89" | Large |
| Optima 880 | 89" x 89" | Large |
| Ramona 680 | 89" x 89" | Large |
| AIRCAP 1™ X-Large · fits 92"–94" | ||
| Hamilton 780 (2012 and earlier) | 92" x 92" | X-Large |
| Hawthorne 680 | 92" x 92" | X-Large |
Your cover. Your way.
The Spa Fitter matches the current models of every major brand to the right AIRCAP 1™ — or measure any square spa with SureFit™.
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Available in over 120 authorized hot tub showrooms across 34 states.