What is the vulcanization?
While military style combat boots may look like common boots, they are not built like the average boot. Combat boots are designed and engineered with the safety and comfort of the soldier in mind. They are durable and flexible, waterproof and lightweight, the perfect footwear for combat or training in any weather or environment condition. They are manufactured to meet all military specifications for uniform compliance, ruggedness, and durability, depending on the specific operating environment. Military boots support the ankles of the wearer to prevent injury or strain but are flexible enough to enable movement, thus allowing for a good range of motion and reducing fatigue. Each boot is designed for a specific surface ranging from wet smooth surfaces to cold, rocky ones. In their own intended setting, each boot is designed to provide good traction and grip.
There are four main parts of the combat boot: the leather and nylon mesh upper, the comfort insole, the soft midsole and the hard outsole. Because of the long wear design of combat boots, the hard leather upper is broken up with patches of nylon mesh to promote ventilation and cut back on perspiration. Along with patches of nylon mesh, the boots are primarily constructed of thick, hard grain, rough out leather (which is water proofed) to protect the soldier's feet from any kind of attack in combat and from possible falling debris and ground threats. The stiff leather also supports the soldier's ankles and feet during intense physical activity such as climbing or running.
There is a special insole in most combat boots which is designed to help with ventilation and perspiration, but also to increase the comfort of the boots. The insole will mold to the feet of the wearer and provide internal support to fight against fatigue, blisters, and other concerns of long wear shoes. The insole is also designed to increase traction within the boot so that socked feet do not slip around inside the shoe. The insole is removable and can be replaced if its performance decreases or it becomes damaged.
Beneath the specialized insole, there is a soft rubber layer, the midsole, which absorbs shock and promotes comfort when the boots are worn continually, for long periods of time. It is not replaceable and if it is damaged, the damage is permanent and can affect the performance of the boot. After the soft rubber layer, there is a hard rubber sole the outsole, that is built to last a very long time and to protect the feet from the impact of rocks and other sharp objects that the wearer may come in contact with during active duty or training sessions. It also helps to give the soldier an edge in hand to hand combat when boots are also used as weapons. If the bottom, hard rubber sole wears away, it will leave the soft rubber midsection exposed. The bottom sole needs to be replaced before that point so that the soft rubber is not permanently damaged.
Combat Boots - http://en.wikipedia.org/wiki/Combat_boot