Now this isn't one of the hardest puzzles that I own, but I do think that it is definitely one of the best looking:
As you can see from the photo on the right, this is a simple six-piece burr which was made by the US weapons manufacturer Kel-Tec to celebrate their 15 year anniversary. The pieces are beautifully machined from solid brass to resemble bullets, and the key piece is engraved with the company name and '15 YRS' to show the occasion.
The brass isn't coated in any way so it will dull with age, but I think it is the best way that it could've been made considering the fact that it is meant to resemble regular ammunition, and I think it does that very well. I was actually a little worried about it coming through customs from the US considering what it looks like, but either they could obviously tell that they weren't real, or they didn't have their morning coffee, but they made it through just fine.
As a puzzle it isn't very difficult, as I know this kind of puzzle pretty well I could put it together and take it apart immediately. However if you give it to someone who isn't used to burrs then they may have a harder time trying to do it. I think this should be judged to be more of an aesthetic piece as opposed to a great puzzle.
As far as I'm aware the only way you can get this puzzle is through Kel-Tec themselves. They aren't expensive at all, and you can find them in their online store here: Kel-Tec Bullet Burr.
Many thanks to the great people at Kel-Tec for making this review possible!