MilwaukeeBicycle Co. Polo Hub<span><br /></span><ul> <li>48-Hole</li> <li> 120mm Spacing</li> <li>SUPER Smooth Sealed Cartridge Bearings (comparable to hubs 3 times as expensive)</li> <li> Real Track Nuts</li> Polished or Anodized Black Hi-Flange - with oval cut-outs for that classic look.<br /> <li>Fix/Free Threading - rear hub will accept track cog and lockring on one side and freewheel on the other. </li> <li> 42mm Chainline - to work with track bikes and converting most road bikes to fixed gear.</li></ul><br />For the Wheel Builder:<br /><br /><br />REAR HUB:<br />31.5mm Flange Width<br />61.5mm Flange Diameter