Product Review · Saunas & Cold Plunges · #8 Ranked
Rezvani Frozin 400 Tub
100-gallon roto-molded insulated plunge tub, no chiller · Reviewed by Katie · amazon.com live, Sept 24 2026
Why it scored a 76
The tub-only Frozin 400 is the best-built plunge shell here: roto-molded LDPE, fully foam insulated and made in the USA, which earns Quality 88 and Reliability 84. Satisfaction is 90 on 4.7 stars, but from only 45 ratings. Features stop at 70 because you get a tub and two 3/4-inch ports, nothing to cool the water. At $899.99 Value scores 72, and Warranty is the lowest factor at 40 because the listing states no terms. It makes sense if you already own a chiller or plan to buy one separately.
What you're getting
- 100-gal (400-qt) roto-molded LDPE tub
- Full foam insulation for ice retention
- 48 x 28 x 28 inches; 90 lb empty
- Fits users up to 6 ft 3 in and 300 lb
- 3/4-inch in and out ports fit standard chillers
- Made in the USA
- Tub only: no chiller, pump or filter
- No warranty terms on listing; 45 ratings
ViperScore breakdown
At a glance
- 100 gal, foam insulated
- Roto-molded, made in USA
- Chiller-ready 3/4-inch ports
- Price$899.99
- Tier100-gallon roto-molded insulated plunge tub, no chiller
- Category rank#8 of 10
Should you buy the Rezvani Frozin 400 Tub?
The Rezvani Frozin 400 Tub is for someone who wants a hard, insulated tub and either already owns a chiller or will use ice for now. At $899.99 it ranks #8 of 10 in our Saunas & Cold Plunges category. For $1,050 more, the Rezvani Frozin 400 + Chiller adds cooling to 37°F. The 1stplunge 148-Gal Tub + Chiller Kit includes a chiller for $449.00, though with a soft tub.
Where it earns its score
- Hard shell. Roto-molded LDPE will not puncture the way the inflatable and fabric tubs in this group can.
- Holds cold. Full foam insulation keeps ice longer than an uninsulated barrel or inflatable.
- Chiller-ready. 3/4-inch inlet and outlet plugs fit standard plunge chillers, so you can add cooling later.
- Big-user sizing. Rezvani rates it for users up to 6 ft 3 in and 300 lb.
What to know first
- Warranty is the lowest factor at 40. There are no warranty terms on the listing for an $899.99 tub; ask the seller before ordering.
- Check with your doctor first. If you have a heart condition, are pregnant or take medication that affects heat or cold tolerance, talk to your doctor before any cold plunge.
- No cooling included. Without a chiller you buy ice for every session, and the 1stplunge kit includes one for about half this price.
Our verdict
The Rezvani Frozin 400 Tub scores 76, a Fair Buy ranked #8, on Satisfaction (90), Quality (88) and Reliability (84). Value (72) and Warranty (40) hold it back. Buy it if you already own a chiller and want a tub built to last. If you need cooling in the box, the Rezvani Frozin 400 + Chiller (79) is the same tub with a 0.8 HP chiller.
Rezvani Frozin 400 + Chiller
Questions buyers ask
Does the Frozin 400 tub include a chiller?
No. This version is the tub only. The chiller bundle is a separate listing at $1,949.99.
Will any chiller work with the Frozin 400?
Rezvani says its 3/4-inch in and out ports fit all chillers on the market.
How tall can you be for the Frozin 400?
Rezvani rates it for users up to 6 ft 3 in and 300 lb.
Ready to check it out?
Rezvani Frozin 400 Tub · ViperScore 76 · Fair Buy · $899.99
How the other 9 saunas & cold plunges scored
86Dynamic Saunas Andora 2-Person
84Dynamic Saunas Elite 1-Person
84Dynamic Saunas Heming 2-Person
83Lifepro RejuvaWrap Sauna Blanket
79Rezvani Frozin 400 + Chiller
771stplunge 148-Gal Tub + Chiller Kit
76AudaciaGo XXL Inflatable Plunge
75The Cold Pod 85-Gal Tub
70SereneLife SLISAU30BK Sauna Tent
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