The Grivel Clepsydra is a very unique carabiner. It has a few features that make it perfect as your clip-in for glacier travel. (It comes in two sizes; here I’m featuring the small (S).)

Why is the Clepsydra S great for glacier travel?

• No chance of cross loading means you only need one carabiner to clip to the rope 

• Unique Grivel twin gate means it’s always secure, can’t freeze shut, and can’t wiggle open during a day of glacier tromping. (Yes, the twin gate takes a little getting used to, but you'll figure it out.)

• You can use the small end as a prusik-tender in a hauling system (photo below)

• Small, fairly lightweight

• When you’re not glacier climbing, it works perfectly with a Grigri, as the little “horn” prevents the carabiner from being cross loaded

The standard recommendation for clipping to the rope for glacier travel is to have two opposite and opposed carabiners, at least one of them locking. With the Clepsydra, you only need one.

Before I got this carabiner, I used the Black Diamond Gridlock. This works pretty well, but the screwgate can loosen up over a day, plus as an HMS carabiner, it’s larger than necessary.

Here's how to use the Clepsydra as a “prusik minder” in a hauling system. The small end of the Clepsydra keeps the prusik hitch from being pulled through.