Originally Posted by levain
The Rack Loops are a stand-alone product, so what you see in the photos on the site is what you get i.e. this:
Alloy Hook Straps are included with all US packs of 10 liters and above, and are also available to purchase separately. The older US packs without Alloy Hook Straps will still work with the Rack Loops, but they are a little less conveninent (you'll need to remove one of the male quick-release clips on each straps and thread they through the Rack Loops, then reattach it).
This is no big deal if you're not going to be wanting to ride without the bag attached very often, but the Alloy Hooks are a tidier solution.
The only exception is the US-5, which need to be attached with a set of our Cam Straps
(due to the standard straps being designed to be bolted directly onto the bike and are therefore too short for a Rack Loop application). Like so:
That said, you can attach pretty much attach anything you like with any appropriate 25mm straps. Comme ša:
Hope that helps!