The Aluminium Hedgehog puzzle is in the same genre of puzzles including the Hanayama Cast Cage and Man The Torpedo. All three puzzles are similar in that they require you to remove an object from the puzzle "cage". In the case of the Hedgehog, the object to be removed from its cage is a hedgehog represented by a sphere with 10 rods of varying lengths inserted into it.
My copy of the puzzle came from William Strijbos and is entirely made of polished aluminium, both the cage as well as the hedgehog. Quality is very good and even the insides of the cage is pretty well finished with virtually no rough edges. The puzzle measures about 70mm tall with a diameter of 50mm. The cage is made from five openings cut into an aluminium cylinder covered at the top and bottom. The size of this puzzle is really nice since it is large enough for the hands to hold it comfortably and I had little problems gripping the hedgehog.
I did not find the puzzle difficult after my previous experience with the Cast Cage and I removed the hedgehog within a couple of minutes. This is not to say that the puzzle is easy; by no means is it so and for the uninitiated handling a puzzle like that for the first time, it may take quite a while to solve it, as was proven by a non-puzzling relative of mine who dropped by for a visit. He was fiddling with it the whole evening and still couldn't solve it by the time he left. (PS-If you need a clue on how to go about getting the hedgehog out, please see my review of the Cast Cage).
Overall this is a fun puzzle which can be solved very quickly and repeatedly once you figure out the initial solution. With its nice shiny polished exterior and relatively large dimensions, it also makes an interesting conversation piece.