These Milward Stretch Twin Machine Needles are designed to allow you to sew perfectly parallel lines of stitching to create seams, top stitching, pin tucks or other embellishments. It's a simple way to create incredibly professional-looking work with wonderful attention to detail. The space between these needles is 4 mm, and the needles themselves are the no. 75 size. When working with these twin needles, it's best to sew at a slower speed to ensure precision. No. 75, stretch4 mm spaceTwin needlesPerfect for stitching parallel linesMilward Stretch Twin Machine Needles No. 75