SMS coveralls are made of a durable, three-layer fabric that protects against light liquid splashes and sprays, while also keeping you cool for extended periods. The durable, three-layer SMS fabric (Spunbond Meltblown Spunbond) protects against light liquid splashes and sprays and provides a superior particulate barrier. The outermost layer of spunbond polypropylene provides strength, while the middle layer of meltblown polypropylene provides liquid resistance via a microporous film. This film also allows air to flow through freely, creating a more breathable garment that helps prevent heat stress. A storm flap over the zipper adds an extra layer of protection, preventing liquids and other contaminants from entering through exposed zipper seams. An attached hood helps protect the neck and shoulders, while secure elastic wrists and ankles work together to keep contaminants from entering high-movement areas.