FSA Orbit C-33 Bearing 1-1/4" Diameter 45x45° Contact Angle Headset Lower Bearing – Steel MFPN=SCO020293S0100 This increases the strength substantially

This increases the strength substantially over frames that use a “sandwiched” top tube at this critical junction

Not recommended for titanium threads

Fits Brand Shimano Drivetrain Speeds 10

Mount Compatibility 110mm/130mm 5-bolt Teeth 48T Type Material AL6061 Spec Color Silver Chain Compatiblity 1/2` x 3/32` Tooth Type Standard Weight Offset

100% Surly Chromoly steel with 44mm headtube and internal dropper post cable routing

FSA Orbit C-33 Bearing 1-1/4" Diameter 45x45° Contact Angle Headset Lower Bearing – Steel MFPN=SCO020293S0100 This increases the strength substantiallyFSA Orbit C 33 lower Bearing 1 1 4 45x45. FSA Standard Headset Bearings