Jeanne, like others said, get your bobbins, #66 from some where like sew-classic. Don't get the Singer #66 bobbins from Walmart or Joann's. Somehow thy don't work as well on the vintage machines as the ones from sew-classic, I know, I tried some from Walmart and they were just a little off in size. If you have low shank attachments for other machines, they should work on your 99. I have 2 of them, a 1924 99 with the large metal foot petal, and a 1928 99-13 that has the knee bar. What year is your 99 from? Your manual should show how and where to oil it. Use sewing machine oil, NEVER 3 in one oil! Happy sewing!