This is a very early transformation of a standard Skewb.
As Ton Dennenbroek writes in the twistypuzzles thread below:
"The Magic Tetrahedron was independently invented by four inventors, Benjamin R Halpern , Kersten Meier and Marko van Eekelen together with Bernard van Houtum . The Magic Tetrahedron is also know as the Halpern-Meier Pyramid. Marko van Eekelen & Bernard van Houtum wrote a paper for there graduation in September 1981, its describes drawings and solutions and mathematical description of the puzzle."
Weight of Tony Fisher's puzzle: 300g
Size: Edge length: 15.2cm