The Bandi chalk bag from Petzl has a round shape with a wide opening to accommodate the entire hand. Its flexible material remains comfortable with a backpack or when you are leaning against the rock, which is always a plus. The closure system of the Bandi by Petzl is practical, thanks to a central tightening by cord and tanka. It can be opened with one hand when you forgot to open it before you started climbing, another major advantage. It's the little things that count.