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 QCA Spas Ruby (2024 and later) takes the AIRCAP 1™ Small — a foam-free replacement hot tub cover for square spas 83"–85". The Ruby (2024 and later)'s cabinet measures 84" x 84", inside the Small'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 Small
Cabinet 84" x 84" fits 83"–85"
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 | 84" x 84" |
|---|---|
| AIRCAP 1™ size | Small fits 83"–85" |
| 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 Small, which fits cabinets 83"–85", covers the Ruby (2024 and later)'s 84" x 84" shell with the right overhang.
At 84" the Ruby (2024 and later) sits mid-band in the Small's 83"–85" range, 1" off the bottom and 1" off the top. Within QCA Spas, the Ruby (2024 and later) shares that 84" x 84" cabinet with Gemstone Deluxe, Island PM (Paradise Island PM), Island XLP (Paradise Island XLP) and Topaz (2024 and later) — same footprint, same cover. The 49 QCA Spas models we fit sit on 7 footprints, and the Ruby (2024 and later) is on number 4 of 7 from the smallest; together they span 5 of the six AIRCAP 1 sizes.
Cabinet dimensions can change between model years. Before ordering, measure your Ruby (2024 and later) 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 84" x 84" is on one page: hot tubs that take an 84" × 84" cover — the same AIRCAP 1™ Small, at the same price.
Dimensions are taken from QCA’s product pages and its 2026 Spa Collection catalog for current models, from its 2024 condensed line-up catalog on qcaspas.com for the discontinued Majestic and Jewel models, and, for older models, from archived copies of QCA’s product pages, its spec sheets for Home Depot and Lowe’s, its dealer catalogs and its replacement-cover listings (September and October 2026). We publish the figure the maker publishes, and we say so — if your own tape disagrees with it, trust the tape and measure in two steps.
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 QCA Spas Ruby (2024 and later) takes the AIRCAP 1 Small, which fits square hot tubs measuring 83"–85" across. The Ruby (2024 and later)'s cabinet measures 84" x 84", inside that band. Measure your spa side to side across the top of the cabinet to confirm before ordering.
Yes — the Ruby (2024 and later)'s 84" x 84" square cabinet falls in the AIRCAP 1 Small's 83"–85" 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 Small 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 7 QCA Spas models that take the AIRCAP 1 Small.
| Model | Cabinet | AIRCAP 1™ |
|---|---|---|
| AIRCAP 1™ XX-Small · fits 77"–79" | ||
| Excalibur | 79" x 79" | XX-Small |
| Libra (GL5) | 78" x 78" | XX-Small |
| Libra 110 | 78" x 78" | XX-Small |
| Scorpio (GL6) | 78" x 78" | XX-Small |
| Scorpio 110 | 78" x 78" | XX-Small |
| AIRCAP 1™ X-Small · fits 80"–82" | ||
| Corsica | 82" x 82" | X-Small |
| Crete | 82" x 82" | X-Small |
| Cypress | 82" x 82" | X-Small |
| Day Dreamer | 82" x 82" | X-Small |
| Day Dreamer NL (Heritage) | 82" x 82" | X-Small |
| Dream Weaver (Kitty Hawk) | 82" x 82" | X-Small |
| Dream Weaver NL | 82" x 82" | X-Small |
| GT-289 | 82" x 82" | X-Small |
| GT-350 | 82" x 82" | X-Small |
| Palmero | 82" x 82" | X-Small |
| Salerno (Yorktown) | 82" x 82" | X-Small |
| Sardinia | 82" x 82" | X-Small |
| Tranquility | 82" x 82" | X-Small |
| Tranquility NL | 82" x 82" | X-Small |
| AIRCAP 1™ Small · fits 83"–85" | ||
| Gemini (2024 and later, formerly E650, M670) | 85" x 85" | Small |
| Gemstone Deluxe | 84" x 84" | Small same cover as the Ruby (2024 and later) |
| Island PM (Paradise Island PM) | 84" x 84" | Small same cover as the Ruby (2024 and later) |
| Island XLP (Paradise Island XLP) | 84" x 84" | Small same cover as the Ruby (2024 and later) |
| Pisces (2024 and later, formerly E550) | 85" x 85" | Small |
| Ruby (2024 and later) (this page) | 84" x 84" | Small |
| Topaz (2024 and later) | 84" x 84" | Small same cover as the Ruby (2024 and later) |
| AIRCAP 1™ Medium · fits 86"–88" | ||
| Charleston (Valletta) | 87" x 87" | Medium |
| Coral (Coral +3) | 87" x 87" | Medium |
| Coral Deluxe | 87" x 87" | Medium |
| Diamond (2026 and later) | 87" x 87" | Medium |
| Diamond Deluxe | 87" x 87" | Medium |
| GT-396 | 87" x 87" | Medium |
| GT-454 | 87" x 87" | Medium |
| GT-500 | 87" x 87" | Medium |
| Garnet (Garnet +3) | 87" x 87" | Medium |
| Grand Bahama XLP (Grand Bahama, Grand Bahama XL) | 87" x 87" | Medium |
| Miami | 87" x 87" | Medium |
| Myrtle Beach | 87" x 87" | Medium |
| Naples (Carolina) | 87" x 87" | Medium |
| Paradise (Paradise XL, Paradise XLP) | 87" x 87" | Medium |
| Pearl | 87" x 87" | Medium |
| Ultra (Paradise Ultra) | 87" x 87" | Medium |
| Ultra XLP (Paradise Ultra XLP) | 87" x 87" | Medium |
| AIRCAP 1™ X-Large · fits 92"–94" | ||
| Aquarius (E850, M870) | 92" x 92" | X-Large |
| Capricorn | 92" x 92" | X-Large |
| Moonstone (Moonstone +3) | 92" x 92" | X-Large |
| Moonstone Deluxe (Moonstone PM) | 92" x 92" | X-Large |
| Supreme PM (Paradise Supreme PM) | 92" x 92" | X-Large |
| Supreme XLP (Paradise Supreme XLP) | 92" x 92" | X-Large |
Your cover. Your way.
Every QCA Spas model we fit is on one page, each with its cabinet size and cover — or open the Spa Fitter for another brand, or measure any square spa with SureFit™.
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Available in over 120 authorized hot tub showrooms across 34 states.