Two crowns marked B
Kronbalka , or boom , - supporting structure or structural element. It is a timber or, more rarely, a pipe, installed obliquely to support other structural elements or performing an independent function in this form. For example, a crane .
Often used as an element of bracket design, supporting another, horizontally located element of the bracket, sometimes called a hoist . The lower end of the crown is always fixed, and the upper end is either fixed, supporting other elements of the structure, or it is used to place a block with a pulley on it.