36 x 45 degree "ACB" bearing measures: 30.15mm ID x 41mm OD x 6.5mm W

Stainless balls with stainless races! These all-stainless bearings offer great corrosion resistance. This bearing is a drop-in replacement for many Trek upper headset bearings.

Fits the following upper head tubes:
--2008-2009 5 Series Madone frames
--2008-2009 6 Series Madone frames
--2008-2011 4 Series Madone frames
--2012+ 4 Series Madone frames
--2010+ 5 Series Madone frames
--2010+ 6 Series Madone frames
--7 Series Madone frames
--2010+ Fisher Cronus Ultimate frames
--Trek Crockett frames

BEARINGS SOLD INDIVIDUALLY