Pronged Snap Fastentrs consists of 4 parts
          
Similar to the Baby (shirt) button
The main diameters Snap Fastentrs  .
  
Appearance.
 

The front part of the button    The inner part of the button
 

To install the button only one device (the diameter of the fixture should be slightly smaller than the diameter of Pronged Snap Fastentrs  ) : this example

or some other round tube, and even cut water pipes Ø 1/2".
Crown buttons peelable fabric in place
Top set the required item
 The selected device is installed click.

Tube keep straight, hammer hard not to be beaten, 3-4 average strike force.

If there is no tube, you can use the nut

In this case, the accuracy of a hammer blow should be perfect, right on the center of the part.
 

Also note that the nut diameter should match the diameter of the details of Pronged Snap Fastentrs , and the height of the nut must be greater than the height of the button detail.