The dimensions of the polyethylene SPE frits are as follows:
57244: 1 ml tube volume, 6 mm frit diameter, 3/32" (2.4 mm) frit thickness, molded frit type
57180-U: 3 ml tube volume, 9 mm frit diameter, 3/32" (2.4 mm) frit thickness, molded frit type
57181: 6 ml tube volume, 13 mm frit diameter, 3/32" (2.4 mm) frit thickness, molded frit type
57182-U: 12 ml tube volume, 16 mm frit diameter, 3/32" (2.4 mm) frit thickness, punched frit type
57183: 20 ml tube volume, 21 mm frit diameter, 3/32" (2.4 mm) frit thickness, punched frit type
57184: 60 ml tube volume, 28 mm frit diameter, 3/32" (2.4 mm) frit thickness, punched frit type
The porosity of the polyethylene frit in the SPE tubes is approximately 20 um. It is nominal, and 15um would still be considered the standard frit
