Are you in the USA ?
Here's what color magnet sheets look like in the US
They're small sheets of
biodegradeable fibers.. which are treated with polymers or other chemicals that attract and trap loose dye and dirt from the wash water. These sheets act like a magnet, absorbing loose color molecules before they can transfer to other garments, preventing color runs and helping to keep whites white and colors vibrant.
Each sheet is about the size of your hand
In the UK they're called Colour Magnet sheets...
you just add one or 2 to each colour wash, andany dye that may run from clothing gets trapped in the colour dye sheets and not on other clothing