This is the Petrolia Pack 28L, our largest top-loading backpack. It's designed for easy access and holds enough gear for a full day on the trail. The main fabric is a strong but lightweight 450 Dinier recycled polyester plain weave with a ripstop version on the bottom for extra durability. And both fabrics have a durable water repellent finish to shed light moisture and snow. The large main compartment holds bulkier items like a harness, shoes, and a rain shell, and has an internal organization panel for small essentials. A quick side access pocket allows you to keep a 15-inch or smaller laptop inside the pack. It's raised above the bottom of the pack so you can set your pack down without fear of harming your computer. The same pocket doubles as a hydration sleeve with a tube port on the top. A zippered stash pocket on the lid keeps a mapper phone within reach and two stretch-woven side pockets carry water bottles. A front stretch mesh pocket expands to hold a sweater or a damp towel after an afternoon swim. Airflow mesh shoulder straps and back panel provide cool all-day comfort under heavy loads, while an adjustable sternum strap and waist belt balance the load. Named after a small town in northern California on the rugged Lost Coast, the Petrolia Pack 28L is our largest top-loading backpack with enough room inside for a full day of work or play.