Hill & Smith Inc. is an industry leading manufacturer of a wide range of transportation safety products. Through the manufact ... uring of our premier MASH-compliant impact attenuator, the Smart Cushion®, our extensively tested & MASH-compliant portable steel barrier, Zoneguard®, and our Work Area Protection product lines of Smart Work Zone Systems, message and arrow boards, and traffic controls, Hill & Smith Inc. is dedicated to advancing Work Zone Safety, ITS, & Roadside Safety nationwide. read more