Banjo Brothers Waterproof Waxed Canvas Cycling Pannier

I love these. I bought one months ago with a bike rack. It holds multiple plastic grocery bags, or one full paper grocery bag. It's waterproof, and secures onto the bike rack reliably. I bought another because the bike rack can hold one of these on each side of my rear wheel, and they are so convenient, they're almost necessary for a bike rider. They come with straps that clip onto each side so you can carry them over your shoulders if you need. They also have side pockets where I keep bike lights during the day or tools.