Shotbag sandbags come in a variety of shapes and weights 25, 20, 10 lbs. They are used for securing the bases of light stands and set walls. They have handles, for hanging on hooks or risers. They have two wings, to allow draping over light stand legs. All told I have 6 in total. 25 lbs-$20, 15lbs-$12, 10lbs-$10. $92 all totalled.
