This 30" Stainless Steel Curved Racking Cane has the same external dimensions as the plastic canes, but has a larger inside diameter, which allows for a smoother, faster flow. Stainless steel is the preferred material for most brewers because it doesn't scratch like plastic can, which could lead to contamination of your brews. This will be the last racking cane you will ever buy. Use 5/16" ID tubing with this racking cane.