The bottom valve pocket: commonly known as: paste bag, is a packaging efficiency, convenient transport packaging ideas under the guidance of birth. Bag of the overall appearance is square, very suitable for stacking transport; At the bottom of the valve port, convenient filling material, easy and sealing. Applied to a new type of green packaging, canned equipment can be divided into: paper-plastic composite valve pocket or multilayer paper valve pocket. Filled in order to convenient, can be punched on the bag body, convenient and gas discharge, prevent the filling bags.