Below you will find our suggestions for the best hiking shell layers for men. The main function of a shell layer is to provide protection against the elements (rain, snow and wind). A shell (outer layer) is usually worn over the mid-layer and base layer. In warm weather the shell can also be worn directly over the base layer as insulation is not required. Shell layer garments include rain jackets, softshell jackets and insulated (waterproof or water-resistant) jackets.