The CrossTac Rear Squeeze Shootng Rest Bag is designed to be a rear squeeze bag for long range precision shooting. CrossTac got tired of using old smelly socks filled with rice, they get wet and soon are a disaster. CrossTac designed an ergonomic zippered rear bag everyone could get into. This rear squeeze bag is oval shaped to ergonomically fit your hand and is very comfortable for extended shooting sessions. The special fabric on these bags only stretches vertically - this means when you squeeze the bag, the pressure causes the bag to go up, doing what you want, rather than out. A wrist strap runs the full length to keep the bag located in the palm of your hand, or you can tether it with some 550 cord to your shooting mat. This bag comes pre-filled with inert solid poly beads - these gave the bag the best ";squeezability"; feel during CrossTacs field tests. You can replace them with any survival fill (lentils, etc.) if you need it.