SAFETY-PIN
Safety-pin intrigues me:
The head, for example, is the epitome of safety
(it shelters the thing that can be potentially lethal)
The tail, however, is another tale
(it holds certain secrets that can hurl the pin out in the open)
Only the head can save the device from becoming a prick
(it is called the head for a reason).
Luckily, the head knows when to sink in
And to make us safe again.