Chalk bags are used in climbing to hold loose chalk or chalk balls, and are usually attached to either the climber or their harness so they can put their hands in for a covering of chalk whilst climbing.
The only real variance in chalk bags is the size and aesthetics, as well as maybe the odd feature difference. Most chalk bags are supplied with a brush loop, a belt strap and are closed with a drawstring to prevent spillage. Larger chalk bags are better for those with larger hands, summer climbing and for use on longer multi-pitch routes where more chalk might be needed.
There are also chalk buckets or bouldering buckets, which have been designed for boulderers, as they tend to have a larger surface area on the base to help prevent them from falling over and spilling the chalk out. Not massively important in the gym but when you're outside where there's rocky ground and wind, it can make a big difference to have a chalk bucket over a chalk bag for your chalk. It's also faster to cover both hands for the big send with a bucket full!
We stock a wide range of adults and kids chalk bags from leading brands such as Black Diamond, DMM and Metolius. We have a cost effective range to suit every budget and more designer lines that look awesome but do cost a little more. Also check out our chalk bucket range, they are great for bouldering and functional too...