We know what you're thinking and the answer is yes. You do need a nano version of your favourite backpack. Clip this onto your backpack or slide it through your belt bag strap for a nano dose of extra storage. Water-repellent Fabric Fabric is water-repellent fabric. Water-repellent Features Designed for: On the Move Dimensions:: 8.5cm x 6cm x 12cm (3.3" x 2.3" x 4.7") CONDITION: BRAND NEW NWT Unused