You are buying a 100 pack of commercial quality shipping bags that all the aquaculture farms use. Don’t be fooled by others passing off bags like what your Sunday newspaper comes in as shipping bags. This is the strongest shipping bags available and will hold up during shipping. I have personally shipped thousands of designer clownfish in the same bags and have yet to lose a fish due to bag failure. Yes, the bags cost more but how much will it cost to have a DOA due to a bag failure? Ship with the best quality bags and use the same ones the pros do.