Schmetz say:
The SCHMETZ Microtex sewing machine needle is generically known as a "sharp" needle. The very slim acute point creates beautiful topstitching on fashion sewing and perfectly straight stitches for piecing and quilting. Use the SCHMETZ Microtex when precision is paramount. Use SCHMETZ Microtex with Micro fibers, polyester, silk, foils, fake leather, batiks, quilting cotton. The very thin acute point creates beautiful topstitching and perfectly straight stitches for piecing quilts.