The Royal National Lifeboat Institution (RNLI)
Their lifeboat crews and teams of beach lifeguards play a crucial role
in keeping the seas and beaches around our coast safe.
This large glass cube is one of their latest ways to try to get their message across to the public.
This one has been located close to Devil's Point, at the mouth of the River Tamar,
where it enters Plymouth Sound.
Here, where the river narrows, the flow of the tides meet flow of the river, producing very treacherous conditions.
Check out their message on other two faces of the water cube. Let's hope it works.