A deep sea fishing reel provides the physical link with the system.
It is mounted on a wooden support on which a pulley provides a friction free running of the line. tests with weight and with an empty housing showed that the system allows reaching > 300 m with reasonable effort and that the line can sustain carrying of a single housing.
A release system, based on the dissolution of salt, releasing a weight was devloped.
In 2021 a new reel was purchased, as the previous one showed significant wear in the ball bearings.