Watch out for thos "just for FW" ads. Cari-in-Oly is right. Just get the lowshank, side clamp one from Sew-Classic.com. Mine works great. It is the 301, slant needle one that has to be designated as "slant" or it WON'T work on a 301 or 5000-503. FWs are easy to fit. Good luck
Donna