This is the standard straight-stitch presser foot included with most all vintage Singer Slant Shank Sewing Machines.  This presser foot is for straight-stitch only.  Do not try to zigzag stitch (if using on a zigzag machine) using this presser foot.

SLANT SHANK:  fits all SLANT shank Singer Sewing Machines (i.e. 301, 301A, 401, 401A, 403, 500, 503, 600 & 700 Series and all other Slant Needle Singer Models)