A great cooler backpack should have the following characteristics:
1. Insulation: The backpack should have high-quality closed-cell insulation to keep your food and drinks cold for an extended period.
2. Capacity: The backpack should have enough space to accommodate your food, drinks, and other accessories. It should be large enough to hold a significant number of items, but not so large that it becomes unwieldy. A good suggestion would be 20-30 cans.
3. Durability: A cooler backpack should be made from high-quality materials that are durable and long-lasting. Look for materials like TPU, PVC, nylon, polyester, or other durable fabrics that can withstand wear and tear.
4. Comfort: The backpack should be comfortable to wear, even when it's fully loaded. Look for padded shoulder straps and a padded back panel that can help distribute the weight of the backpack evenly. The padded back panel also prevents the cooler from sticking to you during hot or strenuous outings.
5. Waterproof: The backpack should be water-resistant or waterproof to protect your food and drinks from rain or other forms of moisture. A waterproof or air-tight zipper is a good option.
6. Pockets and compartments: Look for a backpack that has pockets and or attachment grids or bungees to help you organize your items. This can include a separate compartment for your phone, wallet, or keys, as well as mesh pockets or attachment grids for water bottles.
7. Easy to clean: The backpack should be easy to clean and maintain. Look for a backpack that can be wiped down with a damp cloth or washed with mild cleaners.
Overall, a great cooler backpack should be durable, comfortable, and practical. It should have plenty of storage space, be easy to clean, and keep your food and drinks cold for extended periods of time.