It stays much colder than traditional ice packs with the added bonus of no condesation building up on the inside of the travel box, like no water to make everything soggy &wet? However never take a huge breath of the contents as you open the box or container because inhaling trapped dry ice gas can be very harmful to your lungs! Simply let it mix with the air then carefully use gloves to move any dry ice away from your product and it should still be very frozen. We do this for long distance wedding cake delivery and I've never had one melt, 2 hours or more of driving to the events! Hope this helps!