the Nelson-Rigg Cooler Bag is rainproof without needing an additional cover. It has a leak proof liner with a moveable Velcro shelf. It can keep your extra riding gear dry or keep your sodas cold. Two gallons of milk will fit side-by-side with room for a bag of tangerines on top. The straps are easy to secure and have plenty of extra length if needed. Soft loops at the lower end minimize the amount of hardware, bulk, and abrasion. Having a single compartment just simplifies item search compared to a dozen pockets and zippers to fiddle with. I usually have 2 frozen waters and 2 cold sodas in mine. The elongated rectangle base is ideal for my sportbike rack.