Index finger support and neck safety bumper for the Stewmac fret crowning file (file width 3.85mm, with scaling will fit others just the same). Each support is meant to be printed in two parts, flats go together (glue or not, fit is tight). Variations with and without finger groove stop (raised and rounded off part at the end, also doubles as a bit safer geometry for the bumper meant to be installed right at the end of the file)