I´m not sure if this is known but at least to me it was new that there is an adapter for retrofitting a roller foot to Singer needle feed and drop feed machines which have the "Split Presser Foot Bar". Usually this type of presser foot bars cannot accommodate roller feet. So with this adapter you can install roller feet like the ones you find for the Singer 31K / 331K and similar machines (works best with small diameter roller I think). Quick explanation - I restored a 51WSV2 last year and