Ergodyne - EGO23380 Universal bump cap insert is an impact-resistant shell that inserts into your headwear to protect against bumps, scrapes and bruises. Flexible horizontal and vertical sides of the shell allow it to fit both a variety of hats/caps and head shapes. Trim-to-fit customization makes it easy and convenient to fit into many types of hats, caps and headwear. The insert is made of a lightweight, durable polypropylene and designed with maximum ventilation to provide continuous airflow for breathability without compromising protection. An interior foam offers additional impact protection and comfort against your head. Bump cap insert is perfect for mechanics, airline baggage handlers as well as workers in warehouses, factories, in-home services and other industries that do not require safety hard hat protection but work in areas with low beams, pipes, passageways or other low-hanging obstructions.