Ultrasac 4 mil Contractor bags are 33% thicker than standard Contractor Bags. They are ideal for the toughest clean-up jobs because they are extra heavy-duty and resist tears and punctures. Ultrasac 4 mil bags have a 42 Gal. capacity, come packed 32 bags per box and feature One-at-a-time-Dispensing. These bags are manufactured from recycled materials which are environmentally friendly and help prevent millions of pounds of scrap materials from entering our landfills each year. Color: Black.