HD30 Heavy-Duty Soft Sided Cooler Bag - MBGWhat separates the ENGEL soft sided cooler from the competition is the fact that the ENGEL HD 30 is entirely welded while most of its counterparts are sewn. By welding all seams, warm air is kept out, dramatically increasing the life of the ice or ice packs inside. The welded seams ensure there will be no air or water leaks, and allow the soft sided HD 30 to keep beverages cold for 4. 5 days in 90 degree temperatures, according to an independent