Specifies the types and the dimensions of the gas filling ports of gas-loaded accumulators used in hydraulic fluid power systems. Describes two male ports for filling the gas side of a gas-loaded accumulator. These ports are designated by the following: male port with M 16 * 2 thread in accordance with ISO 261 and ISO 724, which is preferred for new designs; male port with 8V1 thread in accordance with ISO 4570-1.