Dating singer 301a sewing machine
With minor cosmetic differences, these are all essentially the same machine.Singer 66s were full-sized machines, while the 99 and 185 were 3/4 size machines. The 185 had a green body, while the 66, 99, & 201 were black.As the proud owner of six vintage sewing machines, I've learned a lot (and made a few mistakes).
Singer gradually took over the sewing machine market.This was the start of the slant shank machines manufactured by Singer.As the name indicates, the needle bar was slanted forward for greater visibility while you're sewing.They're solid, well-built straight stitch sewing machines.They can do fancy stitches if you buy a zigzagger attachment (note that the ones below is for a slant shank machine, rather than a low shank machine, as the 66, 99, 185, & 201 are). As the name implies, it had an aluminum body which was much lighter than the cast iron sewing machines that came before. It tends to be more expensive than other vintage sewing machines, since it's quite popular.