Grade up the magic by the power of the material
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You display 2-24"" diamond silks, one red and one white. They are tied together and a knot is tied in the center of each silk. Your hand is passed over the silks and the knots visually change places. That's right, the red knot is now in the center of the white silk and the white knot in the center of the red! Another pass of the hand returns them to their original positions. Then, each knot is untied and the silks are shown

This is a stunning visual effect for close-up or stage. It comes complete with silks and detailed instructions.