This is a key component to measuring quality in MMA foam mats, many supply can sell you something that may look the part but may not last. If the mats are higher quality they will bounce back from impact quickly, if not then they are made with cheaper materials and will not last the test of time. Martial Mats will typically last you 4 years or more.
What is 35-45 hardness?
EVA mats can be made to any firmness, i.e very soft for children playing areas to very hard, for example a free weights area.
The standard hardness for martial arts mats is 35-45 degrees.
This measurement is not a sign of quality, just the firmness of the mat. (35 degrees is slightly softer than 45 degrees)
What is density?
The foam density is not in fact a weight but a measurement of mass per unit of volume and it is measured in kilograms per cubic meter (kg/m3)
Basically, the higher the density of foam, the greater level of impact resistance.
The impact resistance is the ability to push back against weight and prevent the foam from bottoming out.
This means that the higher the density, the better the quality of mat.
Points to consider when buying?
Martial Mats always recommends 100kg/m3 as this is very good at not just making a soft landing but more importantly absorbing much of the impact.
We would always recommend our premium grade jigsaw mats at the higher density of 100kg/m3. We believe there is no reason to have any other options as after 7 years of market research, we have come to learn that this is the most efficient specification designed for all uses whilst maintaining safety and durability as well as a competitive price.
If you manage to find cheaper than Martial Mats then please do check with the supplier what the density as well as the elasticity is on par (if in doubt ask for a sample).
As we are sure you will guess it is in fact cheaper to manufacturer lower density mats. Cheaper materials can be added to the mat, therefore lowering the quality of the mat and reducing the life expectancy.