Vintage Singer sewing machine adjustable seam guide with integrated thumb screw. A great feature is the plastic / nylon base so there is less potential to scratch the bed of your machine. Compatible with most older Singer machines including the 15, 66, 99, 128, Featherweight, 301, Rocketeer, Slant-O-Matic, etc. Very nice vintage condition with minor signs of age, rust free. Genuine, original Simanco / Singer part #161172 - May not be marked but guaranteed to be a original Simanco part.