EDIT 9/22/2019: WARNING: Evidently Black Diamond may have stopped shipping these with the Flick Lock Pro, which is what made them great to begin with. I've attached pictures of my flick locks, note that they are constructed with metal, and not plastic. My poles have a lot of miles on them now and they're still good as new, while others with different locks have experienced breakage on the locks very early on.
Prominent backpacker, author, outdoor enthusiast, and CDT/PCT/AT/other thru hiker Andrew Skurka recommends these as "the only collapsible trekking poles worth buying". I'm inclined to trust him.
They're not the lightest poles on the market (though they're extremely light), but if you need trekking poles, and you want them to be collapsible, these are the ones to get.
According to Black Diamond, they had a supply chain issue, and the Carbon Cork trekking poles with "Flick Lock Pro" locking mechanisms were shipped in limited quantities only to REI. During this time, other sellers like Amazon and Black Diamond themselves stocked a version with inferior plastic flick locks which according to Amazon reviews were plagued with issues. The issue has apparently been fixed, and I'm so glad I waited - the metal flick locks on this model are superior.
Do yourself a favor and don't go with twist lock poles - the locking mechanism just doesn't work as well and they'll slip on you. A readjustment every once in awhile to get them back to the height you want them might seem OK, but at the end of the day you're trusting these things to support your weight and slippage from inferior locking mechanisms is a safety issue (not to mention how difficult they can be to adjust with sweaty hands). To me, it's worth spending the extra coin for flick locks, and these poles are the best on the market.
This pair of poles weighs 1lb 2.6oz on my kitchen scale, which is a small weight price to pay if you're somebody who needs (due to bad knees) or likes (due to them making you feel more like a four-legged animal on the trail) trekking poles. Worth the buy.
Premium handling, lightweight pole with natural cork grip and FlickLock adjustable security 100% carbon fiber construction Natural cork grip with dual-density top and breathable, moisture wicking strap Non-slip EVA Foam mini grip extension Dual FlickLock Interchangeable carbide Tech Tips, low-profile Trekking Baskets and Powder Baskets