Rapid Transit (859-5070 Platoon Expandable Tail Bag Bag maintains shape; Has a lined interior; Rain cover included Attached with Heavy Duty Elastic Strap with Hooks; Optional Shoulder Strap available Protective material prevents slipping and marking Side pockets for storing smaller items; Reflective logos Main compartment measures: 16" L X 12.5" W X 8.75" H Standard, 16" L X 12.5" W X 11.75" H; Expanded and Holds 28.67 Liters, 38.50 Liters expanded