Before inserting the bur, you usually press a button. This causes the part of the bur to be fixed and inserted into the bur. When you release the button, it contracts and holds it firmly. But it's the same way of getting rid of it. When you have a diagonal hand, not a straight one. Its Angle is to allow you to locate it and work in the mouth. When using a low-speed handpiece, it is usually used by cleaning and dentists, and using bols with latches.
