Mammoth soft-sided coolers provide a lightweight and flexible solution to meet the demands of an active lifestyle. All Mammoth premium soft-sided ice chests are made with puncture and tear resistant TPU material using waterproof welded seams for a dependable, high-quality finish that lasts for years. Each cooler is designed to meet the demands of multiple recreational activities and perform great while camping, boating, hunting, fishing, hiking, and at sporting events. Mammoth soft coolers and backpack coolers won’t leak and are lined with thick, high-grade insulation to keep ice up to 3-5 days. Mammoth Trooper 30 Cooler Backpack allows for a convenient way to transport your items in any climate or activity and ensure they arrive securely, but more importantly, dry. To get the optimal ice retention from your Mammoth Soft Cooler: 1. Keep your Coastland in a cool dry place or pre-chill with ice 2. Pre-chill contents going in the cooler 3. Use the coldest ice possible (using multiple types of ice will yield the best results - block ice on bottom and cubed ice on top) 4. Avoid large air spaces in the cooler - fill space with contents or ice when possible 5. Keep the cooler closed