Vintage Singer sewing machine buttonholer attachment template, your choice of size. These templates are compatible with both low and slant shank buttonholers including the Singer #160506, #160743, #489510 and #489500. These templates measures approx 1 3/4" in length, they are not compatible with the #381116 Singer Professional buttonholer which uses the larger 2 1/8" long templates.     

• The following sizes would have originally came with your buttonholer, they include the 5/16", 5/8", 13/16", 1-1/16" and 1-1/16" keyhole template.
• Singer also offered additional templates that were sold separately, they include 3/8", 1/2", 5/8" keyhole and 15/16".
• The rare eyelet template can be found HERE