15. Flex Endurance
This test is used to determine the propensity for materials to crack or otherwise fail at flexing creases, particularly in the vamp area.
16. Fuel/Oil Resistance
Fuel/Oil resistance is a measure of the amount of swell in a material in the presence of specific liquids. Lower volume swell indicates better resistance. This information is of particular importance in safety shoes and in those shoes requiring fuel and oil resistance.
17. Gauge
The gauge of a material is also known as the thickness. This information is typically supplied for informational purposes only.
18. Hardware Attachment strength
This test is a measure of the strength of any type of footwear fastening that involves the use of a lace, when it is subject to a force applied by the lace in the same manner as in wear.