Right Lower Battery is an ‘L’ shaped casemated battery. The casemates are surrounded with concrete and earth has been placed over the top. The embrasures are protected by iron shields with mantlets. There is a shell and cartridge store in a traverse between each pair of guns.
The only plans located for Right Lower Battery date from December 1886 and no details are available concerning the dates or cost of construction. This casemated battery with four 10-inch RML guns was one of the principal coast battery in Fort Camden and it was built by 1870. However, in 1870 the whole of Fort Camden had only two 10-inch RML guns, and it is not know if they were in the Right Lower Battery or Right Upper Battery. By 1873 the addition five 10-inch RML guns had arrived, giving three 10-inch RML in Right Upper Battery and four 10-inch RML in the armoured casemated of Right Lower Battery.
In 1900 the four 10-inch RML guns were removed and the location used as an engine room for the Defence Electric Lights, Brennan Torpedo Station and Submarine Mining Station.