PE Filter Elements ROTI®XBond, for Empty SPE Columns 12 ml, 100 unit(s)PE Filter Elements ROTIXBond, for Empty SPE Columns 12 ml, Thickness, 2. 5 mm, diameter, 15. 8 mm, pore size, 20 m Material: PE. Further attractive products to complete your chromatography laboratory can be found on our Chromatographypage! Technical Information Designation PE Filter Elements Version for empty SPE PP columns 12 ml 15. 8 mm Pore size 20 m Thickness 2. 5 mm Material PE