It is not the most exciting thing I have ever bought, but for your convenience we now carry Schmetz needles for stretch knit fabrics. Twin needles too! They are on the Notions page.
When sewing with knits, it is important to use new, ball-point needles. Synthetic fibers are especially hard on needles and you will find yourself going through them pretty quickly. Otherwise, you will experience skipped stitches, needle holes, snags and runs. So next time you order some knits, pick up some extra needles, just in case.
