An impact attenuating helmet including an outer liner having an inner mating surface, an inner liner positioned under the outer liner and having an outer mating surface configured to be received by the inner mating surface of the outer liner, the inner liner and the outer liner being configured to move relative to each other along a slip plane between outer mating surface of the inner liner and the inner mating surface of the outer liner, and one or more securing attachments, each securing attachment being coupled to the outer liner and being configured to secure the outer liner to the inner liner, each securing attachment comprising a slack element configured to permit a range of movement between the outer liner and the inner liner.