Oakley Sphaera Slash review: sealed against everything, including air

Unit tested

OO9499-03 (949903)

As configured

Matte Transparent Stonewash frame, Prizm Sapphire Polarized lens.

Lens curvature

Dual axis

Temples

Wraparound, thin and plasticky at the rear

This reviews the Oakley Sphaera Slash as a model. The unit above is the exact one tested; other colourways differ in paint and fitted lens, not in anything scored here. Lens tints and coatings are deliberately not part of this review, they are measured and scored separately in the lens research section.

Reviewed by Ken. Full disclosure: I run BananaOptics and I make prescription inserts for most of the frames in this series. Read the prescription section knowing that. Every frame is scored by me, on my face, against published anchors: each criterion is calibrated by the named best and worst frame in the collection, whole points 1 to 10. The full methodology.

Verdict

The Sphaera Slash does one thing better than almost anything I own: it seals. No air comes in. That same sentence is also its biggest weakness, because no air coming in means reduced ventilation, and the wraparound that grips so well presses at the back of my head in a way the Radar EV never does. The rear temple sections are thinner and more plasticky than the Radar's, and after a while you feel it. Great protection, really good grip, compromised comfort. Some people call this the Radar EV's successor. I do not, and the temple execution is why.

Scores

The frame

First, the name, because Oakley made this confusing: the Sphaera Slash, OO9499, is a different frame from the Sphaera, OO9403. If you are shopping, check which one is in front of you. It is a dual axis shield with wraparound temples: curved around your face and down it, sitting close, hooked behind your head. The full close fitting formula, with everything that follows from it.

Size against the Oakley Radar EV Path

The Radar EV Path is the frame this one is gunning for, so it is preloaded here. Look at the temples: that execution difference is the story of this review.

Protection

Very great, and I mean that literally: no air comes in. Close fit, dual curvature, sealed edges. If protection is your first criterion, this is the frame that delivers the most of it.

Grip

Really good. The wraparound holds it on the head through anything, no sliding, mountain biking included.

Ventilation

Reduced, and it follows directly from the protection score. The same seal that keeps the wind out keeps the air in, so fogging risk on climbs and at stops is real. One physical property, two criteria, opposite signs. This frame is the cleanest illustration of that trade I own.

Comfort

The weak point, and clearly worse than the Radar EV. The wrap presses at the back of my head. Put both frames' rear temples side by side and you can see why: the Radar's are thick, round and fully rubberised, the Slash's are thinner, flatter and more plasticky. Same wraparound concept, and this is the version that concentrates pressure instead of spreading it. My cheeks can also touch the lower frame edge when I squint.

Style

Looks good, and the dual axis curve reads as a genuinely cool effect that a flat shield cannot give you. The arch on the side threw me at first: it turns out to be a design element carrying the line from the lens through to the temple, and the shape needs it. It grew on me, and now I think the frame would look wrong without it. Some consider this the follow up to the Radar EV. I understand the reading, the family resemblance is real, but I disagree, and the comfort section is my argument.

Quality

Oakley baseline, with one exception: the rear temple plastic feels cheap for the price, and next to the Radar EV it is visibly a step down.

Prescription

Tight. There is very little space behind the lens, so an insert only works if the maker deliberately designs clearance between face and frame. This is exactly my field, so read it as a disclosed opinion: I build that clearance into my Sphaera insert, and I do not know of a competitor who does. Unlike the Jawbreaker, where the room is simply there by geometry, here it has to be engineered.

My Sphaera insert is where I build in exactly the clearance this section describes. One honest caveat: the Slash is a different frame from the Sphaera OO9403, and I have not confirmed the fit in the Slash yet. Ask me before ordering it for this frame. The Oakley inserts collection.

Ecosystem

Available but not easy, much like the Radar EV. Replacement lenses exist and you will find them if you go looking, you will just pay a bit more for the privilege. Solvable rather than good.

Who should buy it

Riders who want maximum protection and modern looks, and whose heads get on with the wrap, which mine does not entirely. Try it for a full hour before deciding, the rear temples reveal themselves late. If comfort at the back of the head matters more than having the newest shape, the Radar EV Path does the same job with better manners.