Puck's flute was a magic flute crafted by Puck. It resembles a simple tube with holes carved on one side, but it is not clear what the flute is made from or how it is played. The powers of the flute are as yet unknown.
Greg Weisman had intended for the flute to reappear in "The Gathering Part Two", in which Puck would have used the flute to temporarily subdue Oberon. He has said that not using the flute again was probably a mistake.