Wow...wish I'd gotten one of these a long time ago...got this medium sized 'Grizzly' Bean Bag. (note: lettering on the website product photo looks pink but it's actually red) Have used it a couple times now and it is amazing how rock solid steady it holds a camera & lens. For a filler there are almost weightless Styrofoam pellets made for it in case somebody want to carry one around with them. But when they arrived I immediately knew I wouldn't use them...I don't plan to carry it around...will use it in the car or window sill of the house, etc...and don't want the thing as light as a feather blowing off the window as soon as I lift the camera. If not carrying it around you can use practically anything...sand, popcorn, sunflower seeds, rice, beans...or what I used which was 10lbs of Aquarium Gravel I happened to have on hand. Sits in place like the Rock of Gibraltar and nestled / held my Canon 300 and NEX-7 rock solid still for the 2nd photo below.