This iridescent thread is made from mylar and provides light coverage on your canvas.  It can be used alone or stranded with other fibers.  It is a filament weight thread, relatively the same thickness as Accentuate. Use a very long strand and double it through the needle on 18m for open and closed work.  Think insect wings or windows, glass container, etc.. .Best to stitch on a taught canvas on stretcher bars.  225 yards to a spool.