As a light-weight anti-aircraft (AA) gun in some ships; up to six M2 guns could be mounted on exactly the same turret. The GAU-eighteen/A is a lightweight variant of the M2/M3 which is applied on the USAF's MH-53 Pave Minimal and HH-60 Pave Hawk helicopters. These weapons utilize the M2HB https://browningfirearmstoreusa.com/rifles/browning-lever-action/