It is stated on the Arrow Wiki that the bow which Oliver uses has several modifications and that
"The new Oneida Kestrel Compound Bow has a device that allows him to pull arrow hook by an automated way, thus being able to climb on flat surfaces in a matter of seconds."
But has the modifications and the pulley device been shown?
The bow that Oliver shoots in the show, as of Season 2 when he got a fancy upgrade, is an Oneida Kestrel, which is not actually a compound bow. Rather, it's a very high-tech recurve bow (because of the shape of the bow stock), but has the cams that you usually associate with compound bows. Oliver's bow has also been modified to be collapsible, mostly so they can do the cool "shake my bow open" shot every so often.
In-universe, there has been mention of "other enhancements" to the bow, but never elaborated on, and as far as I can tell, the bow's shape and cam system are the same as on the real Kestrel.
The other part you quoted in the wiki is very poorly worded, since it has nothing to do with the bow. It's describing the grappling hook arrow, which Oliver can somehow attach to cable, fire, and set into the target surface without letting go of the bow stock. Oliver has the cable spooled onto a device that he clips to his belt, along with a safety harness hook, allowing him to use the cable to climb or rappel as needed. None of this depends on the bow Oliver is using, because both he and Roy have done so repeatedly on the show, using at least 4 different kinds of bows.
