Comparison : Item # 3C-1900-MFD-P, 3 Inch (in) Port Manual Drain Coalescing High Flow Separator
Item # 3C-1900-MFE-P, 4 Inch (in) Port Manual Drain Coalescing High Flow Separator
Item # 3C-3000-MFF-P, 6 Inch (in) Port Manual Drain Coalescing High Flow Separator
Item # 3C-1900-MFD-X, 3 Inch (in) Port External Automatic Drain Coalescing High Flow Separator
Item # 3C-1900-MFE-X, 4 Inch (in) Port External Automatic Drain Coalescing High Flow Separator