This ingenious innovation from Mammut is always met with excitement from anyone I show it to and skepticism from anyone I describe it to… “it’s kinda like a rock climbers fanny pack, but really cool!”. All kidding aside, the multi-pitch chalk bag is a very functional piece of equipment that helps reduce harness clutter and fills the gap for multi-pitch climbs that are too long to go on without packing a little food, water, a spare layer, etc. but too short to really require a proper pack.

So, what exactly is the multi-pitch chalk bag? Well basically it’s a regular chalk bag with a couple of zippered pockets, a pouch and a bungee cord. A very simple idea that works great because of well thought out design and attention to detail.
First the large rear pocket has two compartments in it which server to hold a few bars, a cell phone (it even fits the massive iPhone 6+), a small camera, sun screen or even a summit beer (barely).
The smaller, low-profile side pocket has a vertical zipper, though anything stored inside is protected from falling out by a small mesh catch at the bottom. This pocket also has a clip for keys. One thing we noticed was that it could get a bit harder to access the chalk in the bag if this pocket was over stuffed as it would push into the chalk compartment.
The other side of the chalk bag has a small, stretchy pouch that works well for items that you want easy access to such as belay glasses or as an easy place to store bar wrappers, etc.
Lastly, a small bungee and clip on the bottom of the chalk bag can be used to secure a small jacket, hat, etc. It can also hold small approach slippers/shoes but it makes the chalk bag a bit unwieldy.
The waist strap for the chalk bag is a standard nylon strap with plastic buckle. While I’ve never accidentally lost a chalk bag because of a buckle failure I would hate to load this thing up with some expensive gear and lose it. To guard against this it’s easy to take the tail end of the buckle strap and tie it across the buckle as a back-up.
Pros: Very functional and well thought out, works great… it can hold a summit beer, dammit!
Cons: A slightly more secure waist strap buckle would be nice due to the additional weight and potentially expensive equipment stored in the chalk bag.
Overall: This chalk bag gets rid of the issue of needing an annoying day pack or having an overly cluttered harness for moderate length multi-pitch climbs. A must-have if you do much multi-pitch climbing.
Mammut supplied a sample for review but that in no way influenced our opinions.