This is what I use to carry my planner when I don't want to take a purse along shopping. I attach a market-type bag to my key ring. I only need to unfold the bag from its holder if I've found something to purchase or if I need to protect my planner by hanging or laying it down inside of the bag. It's made of light-weight nylon and holds a ton of things. I use it mostly at farmers markets, Ikea, the library … any place I go empty handed and may leave with lots of loose bits.