My BC backpack fits like a glove! The clasp is magnetic and closes tightly. Blue is darker than in the photo; not dark blue, but rather Prussian blue. I wish I could go with an orange. It's a nice blue, just darker than I wanted. but it is exactly what I wanted in terms of functionality and I 100% recommend it and will buy it again when the time comes. For reference, my BC is 3 11/16" x 2 5/16"