Made of high quality stainless steel, nickel plated, resistance to compression, corrosion resistance, high performance and high reliability. The 0.5 micron & 2 micron inline diffusion stone(1/4 barb) have millions of tiny pores, so that this diffusion stone will quickly oxygenate wort & carbonate beer/soda prior to fermentation. This diffusion stone can also be attached to the end of your “gas in” on your keg with 50cm of tubing to rapidly speed up carbonation. The diffusion stone can connect with kettle&pump&wort chiller by hose. Perfect for /Seltzer Water Brewing. Specification: Material: Stainless Steel Size: 48x12x7mm/1.89x0.47x0.28inch Package Includes: 2 Piece Micron Diffusion Stone 2 Piece 0.5m Length Hose Note: Please allow slight dimension difference due to different manual measurement.