Metal pall ring 1)special structure 2)Material:stainless steel, carbon steel, aluminum, bronze, 304L, 316L, and other alloy Welcome to our ... 1940s. The pall ring is made of a metal thin sheet and have a special structure, there are two row window ... are available in a wide range of materials such as stainless steel, carbon steel, aluminum, bronze, 304L, 316L, and other alloy etcCharacteristic indexesD ...