The battery supported Fort Perch Rock, which was located opposite on the Wirral bank of the river.

[1] The main armament comprised four 12.5-inch RML guns which were mounted in armoured granite casemates.

These were soon augmented in 1894 with two 4.7-inch Quick Fire guns which were originally sent to arm Fort Perch Rock.

In 1898 a fire control centre for the 4.7-inch guns was added at the east end of the battery.

[3] In 1928, a review of the defences of the Mersey was undertaken and it was decided that Seaforth battery was no longer required.