HFS R Tail Pipe Muffler Exhaust Expander 1-1/8" to 3-1/2" Tool Set with Case Includes carrying case, spare o-rings, and 3 sizes of flare tools Large Flare Expander Tool: 2.10" - 3.25" (53 - 82 mm) Inner Diameter Medium Flare Expander Tool: 1.54" - 2.31" (39 - 58 mm) Inner Diameter Small Flare Expander Tool: 1.15 - 1.70 (29 - 43 mm) Inner Diameter Includes spare o-ring set