2.0mm I.D. guard cartridges are used for columns with 2.1mm I.D. to 3.0mm I.D. (HPLC, SFC & Chiral)
3.2mm I.D. guard cartridges are used for columns with 3.2mm I.D. to 4.6mm I.D. (HPLC, SFC & Chiral) 10mm I.D. guard cartridges are used for columns with
7.8mm I.D. to 20mm I.D. ( HPLC use ONLY ) .
30mm I.D. guard cartridges are used for columns with 30mm I.D. (HPLC use ONLY).