The Atlas features strap mounting with side stabilizers to keep the bag centered durring a ride. Pre-shaped main compartment 10" x 7" x 3" Large pre-shaped compartment with strap mount and side stabilizers The high level fabric used in all Axiom bags has exceptionally low off-gassing characteristics (open up a bag and you notice it doesn"t smell like plastic or chemicals!) that exceed even European standards Water-resistant 600d nylon with reflective trim Item SpecificationsColorBlackTotal Volume323in3