Carhartt men's double-front bibs made of heavyweight firm-hand duck. Armed with two sewing machines, Hamilton Carhartt began producing overalls to help keep railroad workers safe and comfortable on the job. More than 100 years later, our goal remains the same: To create durable workwear for people facing the toughest jobs. These men's heavyweight bibs are made with our firm-hand duck, the strongest cotton canvas out there. They're built to hold their own through wind, light rain, and several seasons of the hardest work.