The Metal Man, who is an identical twin to the Metal Man at Tramore, Co. Waterford, was established on Perch Rock in 1821. In 1934 its character was changed from a single Red flash every 3 seconds to a Double Red Flash every 5 seconds. It was intended to be placed on the Blackrock Beacon but when the merchants of Sligo looked for Blackrock to be converted to a lighthouse the sailor, on their suggestion, was placed on Perch Rock. An acetylene light was established beside him on 16th October 1908. In 1965 its character was changed to Occ W 5 s along with Oyster Island (rear leading light). It was converted to propane on 9th October 1979 and the character changed to Fl W 4secs with a range of 7 nautical miles. On 13 March 2003 the gas powered light was changed to solar powered. The character was changed to Fl (3) W 6.1 seconds and synchronised with Oyster Island. From this date the light is exhibited in hours of darkness only