CHENGYIDA 9- PACK (3 COLOR) Auto Vanishing Pen Disappearing Ink Pen Air Erasable Pen Invisible Ink Adber Chako Ace Dressmakers Marker Pen This pen makes a bright BLUE/PICK/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: BLUE/PICK/PURPLE QTY: 9PC (3PCS PER COLOR)