Front & Rear Bike Boost Hub Conversion (15mm x 100mm to 110mm) (12mm x 142mm to 148mm) Review Posted: July 30, 2018 Under: Bike Hubs By ChillyBoulder no Comments From Taiwan Fouriers brand Material: alloy 6061,CNC made Front 15mm boost hub adpater, Convert 100mm to 110mm Rear 12mm boost hub adpater, Convert 142mm to 148mm Weight: front 11g,rear 10g Front(15mm x 100mm to 110mm), Rear(12mm x 142mm to 148mm)