A highly asymmetric and downturned remake of the sport-oriented Lace-up Diamond, the Ocun Diamond S aims to bring the same power and precision to the bouldering and indoor market, and with Ocun's own Cat 1.5 rubber. The Czech brand make all their shoes in house, and have designed the Diamond S with an ambitious fusion of 'maximum performance, comfort, and precision' in mind - and, with one or two minor caveats, I'd argue they've managed to hit the brief.

In Use

The Diamond S is undoubtedly a shoe that performs best on steep terrain. Whether that's overhanging limestone, the roof at your local wall, or a board in a damp and dingy cellar, the aggressive downturn of the shoe and the precise toe are excellent for digging in to small edges and milking them for all they're worth.

In practice, Ocun's Cat 1.5 rubber excels on these small positive edges, as well as when smearing the whole forefoot on larger holds, only becoming slightly unstuck on those in-between 'smedging' footholds at more vertical and slabby angles. For grabbier and more positive holds, though, the Diamond S performs well whatever the angle.

Fit

Without doubt, one of the standout features of the Diamond S is its comfort. For such a downturned and asymmetrical shoe, I have found it extraordinarily comfortable, almost confusingly so! The seamless heel fits comfortably and doesn't pinch at all, and the elasticated liner gives the shoe a sock-like feeling, with excellent foot-shoe contact throughout, and no significant dead space.

There appears to be some ambiguity as to whether the Diamond S is designed for lower volume or higher volume feet, but for me and my relatively low volume feet, both the toe box and the heel fit well. They're about middle of the road in terms of width. If I were to be critical, the heel - perhaps due to the comfort-oriented padding - could be slightly more snug at the sides when it comes to very marginal heel hooks, but for the vast majority of heel and toe hooks, the Diamond S has more than enough precision.

One thing it took me a little while to get used to was the asymmetry of the Diamond S, with the off-centre point encouraging your big toe to a slightly more central position. Even though this wasn't in any way painful for me, for the first few sessions in these shoes I found this pressure on the outer edge of the toe hard to ignore. Some foot shapes are going to get on with this better than others, and helpfully Ocun are one of the few brands to offer an at-a-glance guide to toe type (for the record, the Diamond S are said to be more 'Cube' than 'Greek' - which is my foot shape - or 'Egyptian'). Now that I've had some time to get used to the shoes - or perhaps because they are now properly broken in - I don't notice that pressure on the outer toe at all.

However, what this does do is compress your toes into single point. When tied together with the 3D midsole, which encourages your foot and toes to curl forwards into a knuckled position at the very tip of the shoe, you find yourself with a toe box that offers exceptional precision and power.

All in all, this unique combination of extremely downturned, extremely asymmetrical, and extremely comfortable makes the Diamond S a particularly attractive option for those looking to make the leap into steeper and more advanced climbing. Whilst Ocun suggest starting with your street shoe size when trying shoes on, I ended up downsizing 1.5 UK sizes for an extra snug fit. As ever, you'll really need go try them on for yourself since all feet are different.

Features

The Diamond features 4mm of Ocun's CAT Rubber 1.5, their stickiest compound, which strikes a nice balance between performance and durability. A decent big patch of rubber over the toe box provides plenty of options when searching for the right depth of toe hook, and the single strap closure - with two potential angles of attachment - allows you to get the shoes on and off nice and quickly, whilst providing some adjustability, albeit not as much as those with more straps or laces.

As with the vast majority of Ocun's offering, the Diamond S is fully vegan. Whilst the shoes do feel relatively robust, I have experienced a bit of delamination of the upper toe patch on one of the shoes, but this hasn't been an issue elsewhere.

Summary

For those seeking powerful and precise shoes for steep and technical climbing, where you really want to use the toe to pull in on the holds, the Ocun Diamond S is a great option. The comfy sock liner and stitch-free heel cup are a welcome addition to the 'advanced' shoe field, where comfort can be a bit hard to come by, and they make the Diamond S a great option for those who are looking for a shoe to help them ease into steeper and more advanced climbing.