Total volumes for the columns range from 1 to 150 mL. Columns come with either polyethylene or PTFE frits in 5, 10, or 20 µm pore sizes. PE frits area available in single- or double-fritted configurations. Double frit columns have two frits one directly on top of the other to provide better filtration and cleaner sample. Use caps for room-temperature reactions and to easily transport columns.