Comparison : Item # C6500-3000-48-1, Nylon 6 FDA Natural
Item # C6500-3000-48-3, Nylon 6 FDA Natural
Item # C6500-3000-48-3.5, Nylon 6 FDA Natural
Item # C6500-3000-48-4, Nylon 6 FDA Natural
Item # C6500-3000-48-4.5, Nylon 6 FDA Natural