The North Face Route Rocket
Climbing packs are a bit like camera bags, it seems you can never have too many. This is because of the Goldilocks effect, you always want the one that is just right for the particular climbing activity you are doing. If the pack is too small, you might not have everything you need, or are forced to clip so many extra things to yourself and your bag that the pendulum effect of things swinging when you move threatens to send you tumbling off of a narrow ridgeline. If the pack is too big, you end up carrying more than you need, or more bag weight and bulk than is necessary. Nobody wants to feel overburdened when they are undertaking any technical climbing, nor do they want to be caught exposed without a shell when the clouds unexpectedly roll in. So you ideally want to have a pack of the right size for each type of climbing adventure you might do.
Enter The North Face's Route Rocket. This is designed to be an ultra-minimalist backpack for multi-pitch rock climbing. Climbing legend Peter Croft was on board for the design of this 16L pack, so it is well-thought out, as you'd expect. The outer fabric is both light and impressively durable, there are multiple attachment points if you want to clip the bag to an anchor, hang it below you while abseiling or clip some approach shoes to the outside while wearing it.
The inner compartment is a fairly simple non-compartmentalised space, though there is a hydration bladder sleeve and the zipper access is well thought out so that it opens wide but also in a way that is unlikely to spill out the contents and send them tumbling down below. There is also a small pocket compartment for smaller quick access items. This has its own external zip access, but also a secondary zip access from inside the main compartment, which is a nice touch.
The carrying harness is fairly simple and minimalist, you don't need much structure or bulky padding in a pack of this size, but the shoulder straps are well-shaped to provide good shoulder movement. Other thoughtful features are the whistle in the sternum strap buckle, plus the back panel is a slightly padded material that also has a false back with several access points so the straps can be completely stowed away for snag-free hauling.
This is a fairly niche-use item, and you probably already know if this is an item you need or not. If you are in need of a pack for this particular purpose (or its near equivalent), then the Route Rocket is a supremely functional and well-considered offering with a useful capacity, low profile shape and at a light enough weight to forget you are wearing it.