The B.A.S.E.™ Case 0.5 is an anodized-aluminum capsule with screw-top cap and O-ring for a waterproof seal. Great for small, essential items that MUST be kept dry such as, matches, medication, flints, small electronics, and much more. Simply place your items into the BASE Case and screw on the top nice and tight. The O-ring seal will keep the items inside nice and dry so you won't have to worry about any moisture seeping in throughout your rugged travels. The BASE Case 0.5 is simple, clean in design, and really gets the job done.