Combat helmets were fitted with one of two different style liners that differed only by the shape of the chinstrap "D" ring mounts and the metal type used in the ring's manufacture.  The liner band was the innermost part of the helmet and the portion to which the leather liner was attached. As an entire unit, the liner consisted of two metal bands and an eight or nine finger leather liner and drawstring. The inside of the liner band was a thin pliable sheet of metal to which a series of flat metal bars were riveted. These metal bars acted as "springs" when interlocked to the thicker outer band of metal. Riveted to the outside of the liner band were two flat metal retainers which held a small "D" ring to which the chinstrap was attached. The chinstrap attachment was constructed in such a way that the "D" ring could swing from front to back to allow the wearer the ability to adjust the chinstrap's position under the chin.

Original liner bands were marked in three different locations. The first consisted of a single two digit stamp on the inside front of the liner band. This number represented the size of the leather attachment (and head size) of the wearer in metric equivalents (centimeters). On the outer left side of the liner band the shell size of the helmet and the leather size was stamped into the metal.  This generally took the form of the size proceeded by the letters "n.A."  For example, a liner marked "64 n.A. 57" would  indicate  that the liner band would accommodate a size 64 shell with a 57 cm head size. On the outer right side of the liner band the manufacturer's name, location, date of production, and/or manufacturing code number was stamped.