Further to Steve's review of walking poles for his Dad. I bought a pair of these last year for £28. I do quite a lot of mountain walking and climbing. Over the I years have gone through several different expensive poles. I prefer the flick lock design to the twist to lock, as I find it much less likely for the sections to slip when you put pressure on them, particularly when descending. So far these poles have proved robust and are as good as ones costing a lot more.
These poles are made from carbon fibre and weigh only 190g per pole. They collapse into a shorter folded length than most other poles. Even if you don't plod up and down mountains, it's worth paying the small extra amount over the cheaper poles.