Prismatic Steel Springs 1L. Springs for filling rectification columns. Packing volume 1 liter. The springs are made of 304 stainless steel and are the most effective column filling. About 3cm of the charge height in the column (depending on the diameter of the column) is equivalent to 1 theoretical shelf, i.e. a 100cm high column, fully covered with springs, gives about 30 theoretical shelves. Before first use, it is recommended to wash the springs in sodium hydroxide solution, and then rinse them thoroughly with water.