This is a M4 bolt modified chin front piece for this full size Halo Helmet. http://www.thingiverse.com/thing:158120 Add 4 of M4 x 12 ( or shorter ) socket head bolts for detail to chin piece. As there were artifacts in the slice from Makerware, the STL file has been flipped and reprocessed through netfabb ( again ). Examination of output appears to show this has addressed the issue. Print will be rerun and checked. M4 bolt modified chin front for Halo Helmet by big_red_frog is licensed under the Creative Commons - Attribution - Share Alike license.