Not quite a released band but still cool to post for documenting purposes.
Prototype Apple Sport Deployment Band, in 42mm red.
The Sport variant of this came in White and Red as far as we know, and the Leather variants, which resemble Classic Buckles but with this Deployment-ModernBuckle hybrid style, came in Saddle Brown, Red, and a weird Hypergrape purple that is almost identical to the Black/Hypergrape Nike Sport Band color. As far as i know theres maybe <15 of these style of bands in total that have been seen in the wild, amongst all the known variants.
In terms of feel, this band is very much early stages still and not all the metal edges are perfect yet, but it is surprisingly comfy on the wrist. Getting it adjusted to the right size is a bit of a pain since the gap where the second piece slides into is very tight, though this could just be because the tolerances weren't yet dialed in. It sticks out quite a bit from the wrist since its effectively 2 layers of sport band with metal mechanism in between. The tolerances on the buttons is great, the locking feeling is very satisfying, and the actual deployment mechanism is a very simple mechanism, effectively just a Y piece that acts as a spring bar with buttons on either end and some locking teeth.
Probably one of my favorite collection pieces. I'm still working on getting the Leather variant of one to show it off up close