Spa Fitter
Alps Spas Q-90 Replacement Cover
The Alps Spas Q-90 takes the AIRCAP 1™ Large — a foam-free replacement hot tub cover for square spas 89"–91". The Q-90's cabinet measures 90" x 90", inside the Large'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.
| Spa cabinet | 90" x 90" |
|---|---|
| AIRCAP 1™ size | Large fits 89"–91" |
| 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 |
Why the Large fits the Q-90
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 Large, which fits cabinets 89"–91", covers the Q-90's 90" x 90" shell with the right overhang. Instead of a rigid foam core wrapped in vinyl, the AIRCAP 1™ uses welded drop-stitch construction (the material of premium inflatable paddleboards): a sealed air chamber that cannot absorb water, so it never becomes the waterlogged, two-person lift that ends most foam covers.
Cabinet dimensions can change between model years. Before ordering, measure your Q-90 side to side across the top of the cabinet in both directions — the SureFit™ guide walks through it in two measurements. If your spa measures between two sizes, round up.
Other Alps Spas models we fit
Not a Q-90?
The Spa Fitter matches 363 models across 25 brands to the right AIRCAP 1™ — or measure any square spa with SureFit™.