This is the production version of the new USE Atom stem, an all-British handlebar-holding contrivance with a host of neat touches. They've been working on this for ages - prototypes were on show at The Bike Show earlier in the year - but the stem's now in production and will be available in October.
The most obvious point of uniqueness is the concealed steerer clamp and domed top - no separate top cap here. Headset adjustment is facilitated by USE's Ring-O-Star Allen key preloading widget, included with the stem. Up the front is a slimline four-bolt clamp, and the stem's finished off with some laser-engraved graphics (including the torque settings for the bolts).
It's a rather lovely-looking thing, and will be available in a panoply of reaches (70-140mm), angles (-6degrees, +6degrees, +12degrees) and bar clamp diameters including standard road and MTB as well as 31.8mm oversize to fit USE's range of Atom carbon bars.
RRP is £85, putting the Atom firmly in the high end of the stem market. Dealer information and stuff at www.use1.com.