CHENGYIDA 3- PACK Purple Auto Vanishing Pen Disappearing Ink Pen Air Erasable Pen Invisible Ink Adber Chako Ace Dressmakers Marker Pen This pen makes a bright Purple mark which lasts 24 - 72 hours and then fades away. Marks may be removed earlier by washing in cold water. Great for quilting and perfect for the short time project and a safe way of marking your fabric. Color: Purple QTY: 3PC