Color Changing Shoelaces by Premium Magic.
The magician displays a yellow shoelace. Pulling the shoelace through his hands, it instantly changes to green! The audience suspects the yellow lace is hidden in his hand. When he opens his hand - there's a red shoelace! The yellow shoelace then reappears in the magician's pocket! Easy to do.
Comes complete with three laces (red, yellow, green) and instruction sheet.
Color Changing Shoelaces by Premium Magic