Anyone who swims year-round knows the moment. You’re out of the water, you’re thrilled with yourself, and then the cold hits your feet and the whole victory lap turns into a rush for the car.
A Bondi-based mum has built a fix for that. The EirWaves Heated Recovery Slides pair a rugged EVA slide with a reusable hot pack that sits in a pocket above your toes. No batteries, no cables, no charging. Just warmth on demand when you’re still standing on the sand.
How it works
The heat comes from a reusable saline hot pack, which EirWaves says is 90% sodium acetate plus 10% other non-toxic components. You slide it into the pocket, then flex a small metal disc inside the pack. That triggers a crystallisation reaction, and the pack warms up within seconds. According to the brand, it peaks at about 54°C and stays warm for roughly 40 to 60 minutes, depending on pack size and the outside temperature. A bigger pack with more liquid lasts longer, and a warmer day stretches the window.
When it cools, you reset the pack by boiling it in water for around 10 minutes, then use it again. Nothing to plug in, which suits a product designed to live at the beach.
The science behind the warmth
The clever part is that the pack stores its heat in liquid form. A gentle flex of the metal disc makes the sodium acetate snap into crystals, and that crystallisation releases the stored energy as warmth, within seconds.
The reset is the reverse. Once the pack has cooled and the crystals have set, about 10 minutes in boiling water dissolves them back into liquid and “recharges” the pack for next time. EirWaves says there’s no fixed lifespan: as long as the pack stays intact, it keeps working, hundreds of times over.
On safety, the brand says the pack peaks at around 54°C, warm enough to ease cold feet but not hot enough to burn. It describes that as the same range used in therapeutic heat therapy for circulation and recovery. The solution is CE and MSDS certified, safe for direct skin contact, and free from the chemicals found in single-use heat products. It’s also reusable, so there’s nothing to throw out after one swim.
Why the heat sits above your toes
Most heated footwear puts the warmth under the sole. The design team behind these slides, Sydney studio Vert Design, did it differently after researching thermal sensitivity across the foot. The pack warms the top of your toes instead.
They also tested electrical and hot-water concepts before landing on the simpler option. The reusable pack won because it works off-grid and keeps the slide light.
Using them in real life
EirWaves Heated Slides’ FAQs answer most of the practical questions:
- Activating it: line the pack’s logo up with the slide, then activate it once it’s inserted. You can also activate it first, let it warm for a moment, then slip it in.
- Sensitive skin: EirWaves suggests testing on a small patch of skin first and wearing a sock as a buffer if you’re sensitive. If you have concerns, check with your healthcare provider.
- Cleaning: rinse with fresh water after salt water, hose off any mud, then air dry completely and store somewhere cool and dry.
- Without the pack: they work as a normal pair of slides. The brand says it’s also working on cold packs for the hot days.
- A leak: if the pack’s vinyl gets punctured, don’t use it or boil it. EirWaves will take it back and dispose of it for you.
- In the box: one pair of slides and one reusable hot pack set. Extra packs and multi-pair bundles are sold separately.
- Safety: the slides and pack comply with CE and MSDS standards, and the full certification documents are available on request.
The wellness angle
While EirWaves Heated Slides uses words like “therapeutic” and “recovery”.I am no marathon swimmer and tended to treat the heat as a comfort feature rather than a medical one. For me, the real appeal is simpler: warm feet make it easier to stay outside after a swim, a surf or a cold morning walk.
The brand also ties into the Waves of Wellness (WOW) Foundation and says 10% of profit supports mental health, which fits the blue-space-and-recovery pitch.
Who it’s for
The slide itself is built to work as a proper everyday slide, with or without the pack. It has a contoured footbed, a rugged EVA sole with real tread for gravel, frost and slick decks, and waterproof construction, so there are no soggy socks or ruined sheepskin. It’s ultralight too, so it packs into a beach bag or carry-on easily.
The slides make the most sense if you swim, surf or paddle through the cooler months, or you spend a lot of time on sidelines and beaches in the cold. They’d also suit campers, sauna and ski-trip regulars, and anyone doing the school run in the dark.
If you’re after all-day warmth in wet weather, a slide with a 40 to 60 minute pack isn’t going to run a full day. The pack is built for the moment after the water, and that’s where it earns its place.
