270Pro PURE Anti-Fog Film — The Honest Field Test

Every so often a bit of kit lands in your kit bag that quietly fixes a problem you'd stopped noticing you had. 270Pro reached out and asked me — as a working technical instructor — to put their PURE Anti-Fog Film through its paces and give an honest, no-filter verdict. Two months of hard everyday use — guiding, teaching and technical diving — and a deliberately abused backup mask later, here it is. Full disclosure: the film was provided free of charge. I wasn't paid, and nothing here was pre-approved — the opinions are entirely my own.

The problem every diver knows

Let's be honest about the enemy first. A foggy mask is one of those small, stupid, universal annoyances that every diver has fought since day one. We've all got our rituals — spit, baby shampoo, the fancy defog gels — and they mostly work. Mostly. But you know the feeling: you don't quite get it right before you drop in, and for the rest of the dive you're stuck squinting past that one maddening patch of mist in the corner. On a recreational dive it's a nuisance. On a deep wreck with a job to do, it's a genuine distraction you don't want.

270Pro's answer isn't another bottle of liquid. The PURE Anti-Fog Film is a thin, precision-cut hydrophilic film that adheres to the inside of your lens and simply stays there — a permanent, reusable anti-fog layer rather than a coating you re-apply before every single dive. It's cut specifically for your mask model, with over 200 shapes in their range, so it's a tailored fit, not a one-size-fits-nobody sticker.

Fitting it — genuinely idiot-proof

I'll be straight: I was braced for a fiddly application with air bubbles and swearing. There was none. You line the film up on the inside of the wet lens, pour off the excess water, and leave it to dry overnight. That's it. The next morning it's bonded, crystal clear, and ready to dive. No squeegee, no heat gun, no spitting in your mask like it's the summer of '69. 😉 If you've ever put a screen protector on a phone, this is far easier — the water floats it into place and the hydrophilic layer does the rest.

Two months on the front line

Here's where a review earns its keep. I didn't baby this stuff — I ran it exactly as I'd run any piece of kit I actually rely on. I fitted the film to my Fourth Element Seeker, in both the clear and the tinted lens versions, and to my Beuchat Maxlux S. Different lens geometries, different jobs. Then I dived them — hard — through a couple of months of everyday Malta diving: guiding, technical dives, and teaching, including some Advanced Wreck courses along the way. Normal working use, in other words — the kind of daily wear and tear that usually does a mask in.

The result: every dive, crystal clear. Not "better than before" — clear. That nagging corner patch of mist simply never showed up. Across dozens of dives, in and out of wrecks, warm water and cold, the anti-fog performance didn't waver. This is the headline, and it delivered.

The abuse test (my favourite part)

Anyone can baby a product for a good review. I do the opposite — I abuse the things I test, which, if I'm honest, isn't exactly a stretch for me. So here's what these films actually put up with:

• The backup mask lived in my drysuit pocket for a solid month, getting battered by bolt snaps and clips every single dive. If anything was going to scratch, peel or lift the film, that was it. Result: zero effect on the lining. Untouched.
• My primary mask got the full disrespect treatment — left out in the Maltese sun, shoved into a fin for transport, and given the occasional "courtesy" rinse at best (salt holds everything together anyway, right?). Result: no discolouration, no peeling, no lifting at the edges. Still like the day it went on.

That durability matters more than the fog performance, in a way. Plenty of products work on day one. Far fewer are still working, unbothered, after a month of genuine neglect and a pocket full of sharp metal. This one is. I'm genuinely chuffed with it.

Why it's a real tool for instructors

Now the bit that moved this from "nice gadget" to "actually valuable" for me professionally. As a technical instructor I carry a backup mask in my pocket on every dive. You barely think about it — until the moment you desperately need it: your own mask floods, or a student's does, and it has to come out and go straight onto a face, right now, no fuss.

Knowing — with 100% confidence — that the mask coming out of my pocket is going to be perfectly clear the instant it's needed is real mental comfort at exactly the moment your attention should be on the diver, not the gear. As instructors we're forever hunting for small tools that stack up into genuine safety margin. Being able to hand a guaranteed-clear mask to a stressed student mid-dive is one of those things that sounds minor and absolutely isn't. That's the angle 270Pro wanted a technical diver to test, and it's the one that won me over.

The little things 270Pro got right

• Colour-neutral clarity. High light transmittance with no colour cast — the film disappears visually. On the tinted Seeker, colours stayed true and there was no distortion.
• Scratch protection — the bonus point. Here's the one that 270Pro themselves picked up on from my video: on a tinted mask, the film doubles as a protector for the tint itself, shielding that internal coating from scratches. Tint coatings aren't cheap to replace, so it's a proper bonus — you're protecting the lens while you're defogging it.
• Sensible materials. It's a non-toxic, plasticiser-free silicone film — professionally tested, and it peels off cleanly if you ever want to swap it. No gunk, no residue.
• Reusable and low-maintenance. A quick clean and it keeps performing. This isn't a consumable you're constantly rebuying.

The honest niggles

A review with no criticism isn't a review, it's an advert — so, in fairness, here are the honest little things to know.

It cures overnight. This isn't a fix you can do on the dock five minutes before kitting up and jumping in — you fit it and leave it to dry overnight. So plan your application the day before a trip, not on the boat.

You might get a faint "sweat" layer at the very start — in the heat. Here's an honest one, and it's very much a warm-climate quirk: kitting up in the Malta sun with a hot face, you can drop in and notice the mask isn't perfectly clear for the first minute. That's not the film failing — that's literally your own face sweating into the mask before you hit the water. A quick flood and clear and it's gone for the rest of the dive. Diving a cold UK quarry? You'll probably never see it. Once you know what it is, you stop giving it a second thought. 😄

It's cut per mask model. This is the one genuine trade-off: because each film is laser-cut for a specific mask, if you own several masks you'll need a film for each rather than one bottle of defog that does the lot. Some people won't love that. Personally I see it the other way — it's made to measure, and that's exactly why it fits so perfectly and performs the way it does. You're paying for precision, not a compromise.

One genuinely useful note for my European readers: 270Pro is expanding into Europe soon, so availability this side of the pond is about to get a lot easier. Watch this space. 😉

The bottom line

I wouldn't be writing this up — and I certainly wouldn't be leaving it on my masks — if it hadn't earned it. 270Pro's PURE Anti-Fog Film does exactly what it claims, survived everything I threw at it, and quietly added a real slice of confidence to my backup-gear game. For technical divers, instructors, and frankly anyone who's sick of fighting a foggy mask, this is a genuine set-and-forget upgrade. Five stars, staying fitted, and I'd happily test whatever they send next.

Have a look at the full range on the 270Pro website or the PURE Anti-Fog Film page — they cut it for over 200 mask models, so there's a strong chance yours is covered. And if you want a straight answer on how it holds up in the real world before you buy, drop me a message — I'll give you my honest field opinion, no sales pitch.

Disclosure: 270Pro provided the PURE Anti-Fog Film free of charge for review. No payment was received and no editorial control was given — this review reflects my genuine, independent experience with the product.