This puzzle is a simple extension mod of a mini East Sheen 2x2. It requires some hands sawing and super glueing so it definitely isn't for the feint of heart, but if you manage get past all that it's a great little puzzle and it's lots of fun to play around with.
I came up with the idea for this puzzle when I saw a penrose pyraminx and thought that it didn't look as good as it could. I wanted to add a bigger fillet on the edge and swap around the mechanism inside from a pyraminx to a 2x2. I ended up adding a chamfer around the edge as well which I really like.
You need a mini East Sheen 2x2 to make this puzzle. If you have one you also need to cut off four of the mini 2x2's corners in order to allow the pieces to fit on the puzzle and then superglue the remainder of the cut off corner onto the puzzle. If you print the pieces you'll get a better idea for what I'm talking about. The puzzle doesn't require a lot of support material but does require some.