Ancestral knowledge of cold plunges begins and ends with denizens of Finland, whose cultural legacy (among many) includes the “contrast bath.”

This healthful practice involves alternating exposure to extremely hot and extremely cold water—we’re talking water of the bone-chilling, skimming-into-ice-at-the-edges variety. Though he practices it pretty much without the hot tub, if you were to ask Wim Hof, he’d aver that cold plunges promote vasodilation, reduce inflammation, boost metabolism, remedy mental fatigue, and all-in-all give you a whooping boost of energy and endorphins. And scientists would concur!

Empava has seized on this burgeoning practice to offer the Hot/Cold Plunge Indoor Tub: an impressive side-by-side model that offers the chill at 37.4 F and the heat at 113 F. Users may seamlessly slip from one into the other.

Ricky Cheng, President of Empava, comments on the comparative advantage of not having to sprint across a frozen lake shore and then skedaddle back to the bonfire: “We’re excited to debut our Hot/Cold Plunge Indoor Tub. It delivers spa-level contrast therapy at home with easy temperature control, no ice, and no hassle.” Hot/Cold is a Best of KBIS finalist. It also appeared on stage as part of the show’s “Design Bites” event.

Also new this year: freestanding bathtubs in glittery iridescent finish. With a 14.55-inch soaking depth, they’re vailable in 67-Inch and 49.2 basin lengths, these feature 28 massage and bubble jets—for just the right degree of tingly. Colors include Cerulean Blue, Silver, Green, Aquamarine, and Diamond. And perhaps best of all—they match the mermaid!

Empava’s Hot/Cold Plunge Indoor Tub won Best of KBIS Silver for Wellness Trailblazer. Get more information at Empava.

To discover more on color trends at KBIS 2025, read about the latest from SMEG.