Howard Leight by Honeywell Leight Source 500 Max Earplugs Dispenser Refill saves time and space and the plugs are made of soft polyurethane foam that provides comfort for long term wear. Earplugs have a bell shape for Max mum ear comfort and its contoured design resists the tendency to back-out of ear canal thus facilitating easy insertion. The soil resistant skin of the earplugs avoids dirt build-up and the plugs useful in automotive, aviation, forestry, furniture manufacturing, landscaping and more.