The Whirl-E-Bird is an old collectable with an innovative feature. It was made by North Pacific Products Company in Bend Oregon back in the 1950s. One of the blades fits into the side of a plastic sleeve that slides along the length of the longer arm. You can make an infinite variety of boomerangs from this novel design. Make a two blader with the dingle arm longer than the lift arm or make the lift arm longer than the dingle arm. Make a tri-blader shaped like the letter "T" or slide the short arm to any position in between. The original cost of this boomerang was 29 cents. This one is mint and is still inside the original packaging. The blades are symmetrically beveled so that this boomerang will work either left or right handed.