There is the external ring that is visible to the eye in the pictures set forth here, but the superiority lies in the internal encased liquid system. The compass is magnetized as usual, but floats freely on " Sestroil".
Henry Browne & Son LTD British Sestral Moore Marine Compass- Gimbaled- Boating
SESTREL Henry Browne & Son Brass/Lead Dual Read Gimbal Ships WET COMPASS
Vintage Maritime Mirror Reflector Type DB Henry Browne & Sons, London, Sestrel
Henry Browne & Son Sestrel Ships Gimble Mounted Compass
