The DMM Boa is one of the biggest locking carabiners available. It is billed as the ultimate rigging biner and is used by climbers and high rope access technicians. The Boa is super strong and super tough so this makes it ideal for paddling. I’ve had two types of Boa as shown below. They are the essentially the same in design and weight but have different locking systems. The one on the left has the traditional screw gate and the one on the right has a lock safe gate system.
Walk into any climbing shop and you’ll be presented with a wide array of carabiners, loads of sizes, loads of shapes, loads of colours and a range of prices.
What ever carabiner you choose to buy please make sure that it is a type that is rated for climbing/caving and that it is suitable for job you will be asking it to do. A carabiner suitable for climbing will have its strength rating forged, stamped or etched on it. It should also conform to the relevant PPE standard (EN 12275, the standard for mountaineering connectors), this again should be present on the carabiner.
There are some really super light carabiners available out there that are great for climbing but could be too easily damaged/compromised whilst on the river. In instances where hauling, belaying or security are required locking carabiners are best. I carry four locking carabiners as part of my kit, but also have a couple of non-locking carabiners in my boat for clipping gear into that can be called into service if required.
The number you should carry is subjective – Mountainbuzz, Pin Kit.