The folk at OceanWatch are seeking help to identify this piece of marine debris. Any ideas?

The team at Tangaroa Blue recently found this device on one of their beach cleans. It was classified as fishing gear but OceanWatch are not quite sure what it is exactly. They’ve had a few guesses but can’t be sure. They would love to know what you think! So if you know what it is or want to have a guess, email them at comms@oceanwatch.org.au.