Stax - Reusable Water-Proof Stacking Containers - Large by Humangearhumangear Stax makes organization a snap. Food, pills, gear, or anything else you need to carry with you theres a humangear Stax container for it! The containers click together with a simple 180 degree twist, so you can customize your storage for any situation. humangear Stax is available in small, medium, large, and XL sets. All containers are leak proof, and each set includes the handy ClipHandle so you can easily clip it to a backpack or belt loop.