An oldie and a goodie!
The magician threads three wooden beads onto two golden laces. The spectator then secures the beads on the laces with a double knot. Much to the surprise of the spectator, though, the beads can be immediately removed from the laces at the command of the magician. The beads penetrate the solid laces without a false move or suspicious sleight. They just seem to melt through the laces.
Easy to do. Complete with detailed instructions and full secret. Beads vary in color. Made in the USA by FUN Incorporated.