Streamlined 15L Daypack The 15L Bullet is a grab and go daypack. One day it&&';;s a trip to the pool, the next you&&';;re stuffing jackets and snacks into your backpack for a day hike. It also makes a solid pack to loan a friend who is new to rucking and thinks their cheap book bag will be just fine - which it will be, till it won&&';;t. If you&&';;re looking for ALL THE WEIGHT, go with a Rucker. If you want streamlined and highly packable, go with the 15L Bullet.