This clever chalk bag from Arcteryx uses a twisting action to open & close the bag. This action makes it so easy to quickly get at your chalk, especially if youve forgotten to open the bag before you start climbing. Simply unpopper the top of the chalk bag & it will fall open with a spiral motion to give you quick dipping. When youre all done, twist it closed & the fabric seals on itself to secure the chalk inside. This revolutionary design means you no longer have to worry about your chalk bag leaking out all over your shoes and especially your lunch! This small size has an opening diameter of 10cm & is perfect for those with smaller hands & needing minimal pack size. The other advantage of this twist closure is that it shrinks the overall pack size of the chalk bag so it takes up less room on your harness or in your pack. The Aperture is supplied with a fully adjustable waist strap for easy donning, & the belt attachment even doubles up as a bottle opener. The reinforced rim keeps its circular shape to make it dead easy to get your hands into the chalk when youre pumped out on the crux. Aperture Twist with popper closure Reinforced rim keeps its shape for quick dipping Polyester fleece lining Adjustable waist belt Injection-moulded belt attachment that doubles up as a bottle opener N630p-HT nylon 6, 6 P40r polyester ripstop Brush holder