1 Pack
24 patches
One person, about a fortnight
€9.99
€0.42 a patch
ADD 1
UV REACTIVE PATCHES
Goes Purple When It's Time To Reapply Suncream.
Wear a patch under your suncream. As more UV reaches it, it deepens from pale to purple — your cue to reapply your suncream.
- 1Patch on first — bare skin
- 2Suncream on top
- 3Sits pale. Deep purple = reapply
- 1Patch on first — bare skin
- 2Suncream on top
- 3Sits pale. Deep purple = reapply
24
patches per pack
UV
reactive ink
1
patch a day, each person
UV REACTIVE
Deepens as UV reaches it
WATER RESISTANT
Handles sweat and a splash — check it's still on after a swim
EASY TO APPLY
Peel, stick and go
SHIPS FAST
Dispatched from Ireland in 1–2 days
HOW IT WORKS
One patch. The whole day.
One patch covers your whole day. Reapply suncream over the top and it fades back — no peeling it off and starting over. New day, new patch.
-
01
Stick On One Patch
Apply a single Alert. patch to clean, dry skin on the wrist, arm, knee or leg.
-
02
Apply Suncream
Apply your SPF 30+ as normal, over your skin and over the patch. The layer on top of the patch is what keeps it pale.
-
03
Patch Settles Pale
Within about 30 minutes the patch settles to a pale lilac. That's how it looks with cream over it — take a look so you know what it should be.
-
04
Deep Purple = Reapply
As UV reaches the patch it deepens toward purple. That's your cue to reapply. Suncream back over the top and it fades again.
The patch never goes completely clear. Even under a generous layer of SPF 50 it sits at a pale lilac. That's normal — you're watching for the shade deepening, not for it to disappear.
Alert. is a reapplication reminder, not sun protection. It does not measure SPF and it does not replace suncream. The patch also sits pale in shade, indoors, or under clothing, where little UV reaches it — so a pale patch on its own is not a sign that you are covered. Always follow the directions on your suncream.
Same arm, same afternoon. Unedited tester photos.
THE SCIENCE
It's the same broad class of technology as photochromic lenses, the glasses that darken in sunlight.
Reapply your suncream over the patch and it fades back toward its palest shade over the following minutes. The change is reversible and can happen several times across a day. One patch, one person, one day. No battery, no charging, no app.
- RESTING STATE
- Pale lilac — SPF30 on top, 30 min later
- REACTED STATE
- Deep purple — no suncream on top
ALERT. UV PATCHES — 24 PACK
A reapply reminder you can actually see.
- Pale lilac when little UV is getting through — deep purple when it's time to reapply
- One patch each, per day — reapply over the top and it fades back
- Water and sweat resistant — check it's still stuck down after a swim
- 24 patches per pack
€9.99
€9.99 = €0.42 per patch
Free shipping — always, no minimum
Secure checkout · 30-day returns · Ships in 1–2 days
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MOST POPULAR
2 Packs
48 patches
Two of you, a full holiday
€15.99 €19.98
€0.33 a patch · You save €3.99
ADD 23 Packs
72 patches
A family of four, three weeks
€20.98 €29.97
€0.29 a patch · You save €8.99
ADD 3Take 2 packs and 20% comes off automatically in your cart. Take 3 or more and it's 30%. No code needed.
FROM OUR FIRST TESTERS
People love Alert.
These are from our first testers, each of whom received a free pack from us. Published with permission, unedited, and not verified purchases.
“Genuinely such a clever product — I was blown away.”
“Brilliant on holiday — told us exactly when to reapply so we never got caught out.”
“Perfect for my interrailing trip around Europe — kept me on top of reapplying the whole way.”
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