Crimsafe is made from 304 Security steel. 316 Marine Steel was designed for use in an environment of differential aeration - where part of the steel is immersed in salt water and part is in open air. In this environment, it would last a lot longer than 304 Security steel before corroding.
On land however, there is no practical difference in corrosion potential, even very close to the ocean. And Crimsafe's Tensile Tuff 304 Security steel has significant advantages over 316 Marine steel in terms of its resistance to cutting and its tensile strength.
The short answer is that small metallurgical differences in the combination of alloys that make them give 304 Security steel more strength and toughness, and give 316 Marine steel higher corrosion resistance when immersed in salt water.
You should note that irrespective of the corrosion properties of stainless steel, the high durability coating that is applied to Crimsafe makes corrosion issues for the mesh almost irrelevant as it is isolated from the environment.
You are already familiar with 304 grade steel, though you might not know it. It accounts for more than 50% of all stainless steel produced and finds its way into many, many applications. Your household saucepans, for example, your sink or your cutlery may all be made from 304 grade steel.
304 has significant strength properties. Beyond cutting your steak, it is used in different types of structures the world over because of its high strength and durability.
In fact 304 is the most demanded steel in the world because it is a fantastic all-around product.