Manufactured a range of products including the gyroscopic compass, loudspeakers, 1948 - factory moved to Watford, England; 1960 - company was sold to the De Havilland division of Hawker Siddeley; Later owned by Vosper Thornycroft; 2000 - merged with TSS (motion sensor and subsea pipe/cable tracker specialist) to develop underwater gyros and using name TSS International, 2008 - purchased by the Teledyne group, now trading as Teledyne TSS International; Some products continue to be sold using the name SG Brown, principally gyrocompass and hand-steering units for military vessels. 2009 - 1 Garnet Close, Greycaine Industrial Estate, Watford, Hertfordshire, WD24 7GL; 2010 - 1 Blackmoor Lane, Croxley Green Business Park, Watford, WD18 8GA