The Kong Puzzle - thirteen piece brass burr puzzle by Two Brass Monkeys

This is a thirteen piece brass burr puzzle made by Two Brass Monkeys. Their description is:- 

'Thirteen notched bars slide and interlock to create a pleasing four pound mass of interwoven solid brass. The puzzle comes disassembled in an aluminium presentation case.  Although the puzzle looks and feels intimidating, we carefully selected the design so that it can be assembled by the determined puzzler.'

I can safely say that this is an intimidating puzzle to the extent that I had to resort to the instructions provided on their website in order to assemble it

The puzzle has been assembled once and has been on display since then. As such it is as new but being brass it has acquired a very slight tarnish and could probably do with a polish.