Secondary the secondary ring ring nut that is used and seen each other most of the time, I have two that are.
1. ring ring resembles a round ipae flat with a hole in the middle is useful is helping to spread and increase adhesion to make space in the thick notnaen hole of the protective material not part is damaged from the pressure of the nut.
2. ring spring ring look like a lightning strike, but Roy ipae raised edges straight seam edges match up cause the joints do not. The benefits of this are similar to ring ring ipae but prevents loosening of the nut screw.
In General, the secondary ring, ensuring both have a different use. Depending on whether we use a nut with a category? If we use a nut with wood, usually with a secondary ring nut to protect the ipae eats into the wood, which will make the best hole of the damaged wood. If a child is always applied to the steel with spring ring to add even more firmly, because iron is always expanding and contraction. From the temperature of the environment changes. Make knots may be loosening screw easily, or, in the case of using knots with a piece of steel that has been frequently, it may cause vibration nut loosening screw easily. Therefore, the secondary ring nut selection to suit most any material is needed.