These special bags contain a third middle layer of finely perforated polyethylene, which filters out the solids in the sample when used in a homogenizer blender. Bags feature a filter layer of finely perforated polyethylene, to separate the liquid and solids, allowing for easy pipetting of the sample. The filter is sealed into the perimeter of the bag on the sides and bottom, allowing the sample to be placed in the bag on either side. The liquid will transfer through the filter, but the solids stay on one side. Capacity is measured in fluid ounces when the bag is closed and tab is folded over three times. Volume and dimensions are approximate; bags should not be used at temperatures above 180