Snap-On Invisible Zipper Foot For Domestic Sewing Machines. Compatible Part Number # SA128 Alternate part numbers : 494620-20, ESG-IZF, RJ-601Z, XC1947002 Allows you to install concealed zippers easily. Parallel grooves on sole of foot holds concealed zipper in place while you sew; perfect topstitching will appear on your garment. Can be used with a 1.6 mm twin needle Compatible with narrow pin tucks. Compatible with all 7mm feed dog machines. Universal snap-on foot Compatible with low shank machines...