Remixed from the CreativeTools fan blade replacement. The CTC replicator duals seem to have a slightly larger fan barrel and this model has been scaled to fit said barrel. these push on with a little bit of pressure. be sure to trim the broken blades down to a smooth barrel for a correct fit and add a little glue to make it hold fast. Check out he original if you havent seen it already here: http://www.thingiverse.com/thing:186979 Without it I would have been left fanless! thanks guys!!