There has been lots of discussion if color catchers work or not. I have just put them to the ultimate test. I washed a Bargello quilt made amost entirely of batiks (16 put of 20 fabrics were batik) that have not been pre washed. The colors range from almost white to very dark navy/purple. I tossed two color catchers in the wash and crossed my fingers. There was no staining on the quilt, but the color catchers were very blue. My next test will be with red colored fabrics. I will keep you posted. My experience with color catchers was positive.