Polyolefin construction is compatible with a broad range of products. Springs and balls are #302 stainless steel. Pump delivers 1 oz. per stroke and can be disassembled for rinsing. Gallon pump fits a 38 mm opening. Dip tube is HDPE and 11 inches long. 2.5 gallon pump fits a 63mm opening and has a 16 inch dip tube.