You can buy the pattern individually or as part of the International Boomerangs collection (5 patterns for 8 Euros).

Boomerang shape with a maple key texture, which is quite easy to work (you only need the cable needle every 8 rows ☺).

Yarn weight of your choice (fingering to aran) - minimum 300m/330 yds - more if you want to make a larger version.

Many thanks to the testers:

covelady
miriamspooner
eharris11
ummashin
missbunt