Bonnet

What does the british word bonnet mean?
Definition of bonnet (Entry 1 of 3) 1a(1) chiefly Scotland : a man's or boy's cap. (2) : a brimless Scottish cap of seamless woolen fabric — compare t...
Why you use extension bonnet in valves?
The extended bonnet allows the valve to be wrapped with insulation without interfering with the handwheel. By increasing the bonnet length the stem se...