Points of attention for using 　　Roller bearing is a precise part. Therefore it should be used carefully. No matter how high performance the bearing is, it can not be obtained by improper use. The followings are the points for attention of use to the bearings. 　　(1) Keep clean the bearing and its surrounding areas 　　It is harmful to the bearing even by tiny dust which can not be seen by human eyes. Therefore it should always keep clean the surrounding environments in order to prevent the bearing from dust corrosion. 　　(2) Cautious use of the bearing 　　Scar or indentation can easily be produced out of strong impact to the bearing in use and become the cause of accidents. It will even be cracked or broken in severe occasions. 　　Therefore special caution should be given to its use. 　　(3) Use the appropriate operating tool 　　It is forbidden to use the current tool in operation. Proper and appropriate tool should be adopted then. 　　(4) Be careful to the rust corrosion of the bearings 　　The sweat in the hands will cause rust in operating the bearings. Therefore your hands should be cleanly washed and dried before operation. You'd better wear gloves in doing the work.