The H1 9.2-inch Gun at Apostle Battery is located on ridge, close to the Command Post and immediately below the Battery Observation Post. The magazines and associated works are all in good condition. The Command Post entrance is next to the gun emplacement and is now used as a telecommunications hub. This was the first 9.2-inch gun emplacement completed in April 1942 with a 9.2-inch gun removed from Lion Battery in Cape Town. With the two 6-inch Mark XIX guns, it operated as the counter bombardment battery.
The H1 9.2-inch gun was a Mark X gun on a Mark 5 mount. This Mark 5 mount was replaced by a Mark 9 mounting in December 1944.
The second 9.2-inch gun to be mounted at Apostle Battery was a Mark X gun on a Mark IX which arrived from overseas in August 1943.
The third 9.2-inch gun was a Mark X on Mark IX mounting did not arrive until October 1945 and was operational in January 1946.
The three 9.2-inch guns were located on the ends of ridges, H1 491 metres, H2 471 metres and H3 572 metres. The guns had maximum effective range of 32,5000 yard at 35 degrees elevation with a supercharge.