PD (Perfect Durability) or Titanium needles are the same great quality of Organ needles with the advantage of having a titanium nitride coating layered on the surface of the needle. With the titanium coating, these needles last up to five times longer than conventional chrome-plated needles. They are more wear resistant which reduces needle breakage, bending and distorting. This is a special version of the 15x1 for embroidery and decorative stitching. It is made to higher standards for longer life It has an oversize eye to reduce stress and tension on the thread. It also accommodates metallic threads for heavier top stitching thread and makes needle threading easier. Ball Point needles are used for sewing on knits; the rounded tip allows the needle to pass between the fabric threads by separating them. Needle Systems: 15x1 ST: HAx1 ST, 705H-E These TITANIUM (PD) PERFECT DURABILITY Organ needles are for home embroidery machines. They have a flat shank and will work in all home embroidery machines such as: Juki, Husqvarna, Viking, Baby Lock, Janome, Brother, Bernina, Singer, Pfaff and more.