Sun Mountain Speed Cart Cooler Bag The Sun Mountain Speed Cart Cooler Bag is designed to fit on Sun Mountain Speed Cart Series push carts, the Cooler Pouch has two zippered pockets ñ one that is insulated and will hold up to six 12-ounce cans. The freezable insert is included with the pack. The original Sun Mountain Cool-Paq has been redesigned and updated, and new Speed Cart Cooler Bag is a must have accessory for your Speed Cart.