Quilting needles for sewing machines, do what they say on the pack. The difference with these needles from ordinary needles is that the eye is the needle is a little bit further from the tip. This gives the machine space to form the stitch in the middle of the wadding. There are five needles in a pack.
Quilting 80 this is what we usually use when we are quilting.
Quilting 90 this can be useful if your sewing machine is skipping stitches.