I have a Singer Slant-O-Matic 500 that I brought in 1963 or 1964. This was one of the feet that was included with my machine. It is a ruffler. Needless to say I have never used this foot. It offers a simple and effective way to make gathered and pleated ruffles according to the manual. Ruffles may be made separately or made and applied at the same time. Hope this helps.