NUNU LAB 320 Gallon Deck Box
Best overall (the only shell bigger than its label) — The largest box of the class, 75 inches long, and the only one whose gallon figure fits inside its own dimensions, on the deepest base of the class (4.3★/1,182, pooled across 29 sizes and colours). The seller of record is a Ningbo storefront named 'Amzaon''. Owners describe walls that bow when loaded and a lid a windstorm opens.
Sold in 29 sizes and colours on this listing (30–320 gal) — this page is the 320 gal, Rattan Black. Check the size before you add to cart.
How to read a Showdown Score™
The only score that counts how often a product breaks, not just how owners feel about it.
- Three parts add up to the score: what owners rate it, how often it fails them, and whether a credentialed tester backed it.
- Bands: Exceptional 8.5 and up, Excellent 7.5, Very good 6.5, Good 5.5, Fair 4, Poor below 4. Every score is dated.
- Price, the warranty and what a link pays us stay out of it.
Good
Good is 5.5 to 6.4.
See why it scored 6.0
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Specs
| Capacity | 320 gal (listing) |
| Exterior volume | 376 gal (75.08 × 34.37 × ~33.7 in; the listing's own height field reads 6.69 in, a data error) |
| Material | Resin (listing) |
| Lid | Piston-assisted, lockable (lock not included) |
| Bench rating | Not stated on the listing |
| Warranty | Not published |
| Owner rating | 4.3★ / 1,182 |
Pros
- The only 300-gallon-plus box on Amazon whose claimed capacity fits inside its exterior volume — 75 inches long against the 58–68 inch shells sold as '320' to '380'
- The deepest owner base in the class, 4.3★ across 1,182
- Sold in 29 sizes and colours from one listing, so the 320 can be matched to smaller boxes of the same look
Cons
- Sold by a storefront named 'Amzaon'' — a Ningbo e-commerce company trading under a misspelling of Amazon's name; the brand has no website (nunulab.com parks to a lander) and publishes no warranty
- 'Wind blew it open and the plastic snapped all the hinges, pretty cheap brittle plastic' — the seller replaced it; another owner: 'the cover can blow open with strong winds. The piston isn't real strong'
- 'The walls bow out and cause the bottom to come apart' when loaded with cushions; assembly parts 'not all marked', 'wouldn't click' — 122 critical reviews (10% of the base)
- The rating pools 29 variants from a 30-gallon box up; reviews of 33- and 35-gallon units sit on this page
The shell is not rigid and the lid is not wind-safe. 'The walls bow out and cause the bottom to come apart'; 'really flimsy at the bottom where the walls are attached'; 'Wind blew it open and the plastic snapped all the hinges'; 'the cover can blow open with strong winds. The piston isn't real strong to hold it shut'. Assembly: 'the parts are not all marked', 'wouldn't click', 'took me 45 minutes'.
10 critical read 2026-09-17 of 122 critical on a 1,182-rating base (10%); flimsy/bowing structure in 4, wind and lid in 2, assembly in 4; dates Sep 2025 → Sep 2026; 10/10 Verified Purchase, 0 Vine; variant lines on the page include 33- and 35-gallon units. · critical reviews read September 2026
FAQ
Who is the NUNU LAB 320 Gallon Deck Box for?
You want the biggest box in the class and you have checked who is selling it: 75 by 34 inches of resin, a 4.3★/1,182 base, and the one 300-gallon-plus claim on Amazon that fits inside the box's own exterior volume (376 gallons). Not for you if a lid that can blow open in wind is a deal-breaker — that is its tail.
What do owners say about the NUNU LAB 320 Gallon Deck Box?
4.3★ across 1,182 owner ratings (Amazon, read September 2026 · listing-wide base). What owners complain about: The shell is not rigid and the lid is not wind-safe. 'The walls bow out and cause the bottom to come apart'; 'really flimsy at the bottom where the walls are attached'; 'Wind blew it open and the plastic snapped all the hinges'; 'the cover can blow open with strong winds. The piston isn't real strong to hold it shut'. Assembly: 'the parts are not all marked', 'wouldn't click', 'took me 45 minutes'.
What is the warranty on the NUNU LAB 320 Gallon Deck Box?
NUNU LAB publishes no warranty term for the NUNU LAB 320 Gallon Deck Box — we looked for one from the maker and record the absence rather than guess. Buy it somewhere with a return window you trust.
Does the NUNU LAB 320 Gallon Deck Box come with a manufacturer warranty?
NUNU LAB publishes no warranty document anywhere we can find, so there is no manufacturer term to hold them to beyond the listing itself and the marketplace's own returns window. Nobody can check what does not exist — that is the finding rather than a gap in our research.
Record
- — Added as best overall when the 300-gallon-plus roundup shipped: 4.3 stars across 1,182 pooled across 29 sizes and colours, sold by a third-party storefront named Amzaon', with a lid that owners say wind can open.
Warranty — and what changes if you buy it on Amazon
NUNU LAB publishes no warranty term for this product. We looked for one from the maker and record the absence rather than guess.
NUNU LAB publishes no warranty document anywhere we can find. There is no term to hold them to beyond the listing itself and the marketplace’s own returns window. Nobody can check what does not exist — that is the finding, not a gap in our research.
✓ Safety: no active recall — CPSC recall API checked 2026-09-16: ProductName=deck box → 0 records, ProductName=NUNU LAB → 0 records, with the positive control ProductName=heater returning 181 records in the same sitting. CPSC's long-standing guidance on storage chests concerns freely falling lids that can trap a child; this box has a lockable lid and a lid that holds itself open. Lock it when small children play nearby, and never let a child climb in.
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Data last verified: September 2026. Ratings are real, dated reads — never scraped or invented. Full methodology and monetization disclosure: how we test.