FW stands for a Singer Featherweight sewing machine. They are old, light weight, little, cute machines! I understand they come in white, black and other colors. White and black being the most common, so to find a colored one is rare and worth more money. E-Bay has lots of them for sale, but people are asking a lot of money for them. I saw my first one at an antique store for $450!!! Later my sister gave me one she had purchased years ago, because she never uses it anymore. (She's a foster mom to special needs teen children.) I use mine for piecing. It has a very distinct sound to it. Very very cool little machines. If you do a search on here or google them you will see pics.