Spa Fitter
Master Spas LW 730L Replacement Cover
The Master Spas LW 730L takes the AIRCAP 1™ Small — a foam-free replacement hot tub cover for square spas 83"–85". The LW 730L'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.
| 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 |
Why the Small fits the LW 730L
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 LW 730L's 84" x 84" shell with the right overhang.
At 84" the LW 730L sits mid-band in the Small's 83"–85" range, 1" off the bottom and 1" off the top. Within Master Spas, the LW 730L shares that 84" x 84" cabinet with Balance 7, CS Cape Cod, CS Exeter and HL 7 — same footprint, same cover. Master Spas builds the 45 models we fit on 4 footprints, and the LW 730L is on number 2 of 4 from the smallest; the line spans 4 of the six AIRCAP 1 sizes.
Cabinet dimensions can change between model years. Before ordering, measure your LW 730L 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.
How the AIRCAP 1™ is built
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.
Every Master Spas model we fit
| Model | Cabinet | AIRCAP 1™ |
|---|---|---|
| Balance 6 | 78" x 78" | XX-Small |
| Balance 6 CS | 78" x 78" | XX-Small |
| HL 620L | 78" x 78" | XX-Small |
| HL 630L | 78" x 78" | XX-Small |
| L6 | 78" x 78" | XX-Small |
| LH 6 | 78" x 78" | XX-Small |
| S6 | 78" x 78" | XX-Small |
| TS 6.2 | 78" x 78" | XX-Small |
| Balance 7 | 84" x 84" | Small same cover as the LW 730L |
| CS Cape Cod | 84" x 84" | Small same cover as the LW 730L |
| CS Exeter | 84" x 84" | Small same cover as the LW 730L |
| HL 7 | 84" x 84" | Small same cover as the LW 730L |
| HL 7.5 | 84" x 84" | Small same cover as the LW 730L |
| LH 7 | 84" x 84" | Small same cover as the LW 730L |
| LH L7 | 84" x 84" | Small same cover as the LW 730L |
| LH S7 | 84" x 84" | Small same cover as the LW 730L |
| LSX 700 | 84" x 84" | Small same cover as the LW 730L |
| LW 730L (this page) | 84" x 84" | Small |
| LW Enterprise | 84" x 84" | Small same cover as the LW 730L |
| LW Inspire | 84" x 84" | Small same cover as the LW 730L |
| MPL 700 | 84" x 84" | Small same cover as the LW 730L |
| Precision 7 | 84" x 84" | Small same cover as the LW 730L |
| TS 7.2 | 84" x 84" | Small same cover as the LW 730L |
| TS 7.25 | 84" x 84" | Small same cover as the LW 730L |
| Bar Harbor LE | 86" x 86" | Medium |
| Bar Harbor SE | 86" x 86" | Medium |
| Balance 8 | 94" x 94" | X-Large |
| CS Portsmouth | 94" x 94" | X-Large |
| CS Windsor | 94" x 94" | X-Large |
| HL 8 | 94" x 94" | X-Large |
| HL 8 DL | 94" x 94" | X-Large |
| HL 8.5 | 94" x 94" | X-Large |
| LSX 30 | 94" x 94" | X-Large |
| LSX 800 | 94" x 94" | X-Large |
| LSX 850 | 94" x 94" | X-Large |
| LW Acclaim | 94" x 94" | X-Large |
| LW Intrepid | 94" x 94" | X-Large |
| MPL 800 | 94" x 94" | X-Large |
| MPL 850 | 94" x 94" | X-Large |
| MPL LSX 30 | 94" x 94" | X-Large |
| Precision 8 | 94" x 94" | X-Large |
| TS 8.2 | 94" x 94" | X-Large |
| TS 8.25 | 94" x 94" | X-Large |
| TS 8.3 | 94" x 94" | X-Large |
| TS 8.35 | 94" x 94" | X-Large |
Master Spas LW 730L cover: common questions
What size hot tub cover fits the Master Spas LW 730L?
The Master Spas LW 730L takes the AIRCAP 1 Small, which fits square hot tubs measuring 83"–85" across. The LW 730L'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.
Will the AIRCAP 1 fit a Master Spas LW 730L?
Yes — the LW 730L'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.
How much does a replacement cover for the Master Spas LW 730L cost?
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.
How heavy is a replacement cover for the Master Spas LW 730L?
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.
Not a LW 730L?
The Spa Fitter matches the current models of every major brand to the right AIRCAP 1™ — or measure any square spa with SureFit™.