If the head of the screw to give with the help of nalilsya the form shown in the figure, then any attacker will not be able to turn. On such hardware it is recommended to set sensible things sailing and motor boats, hook locks.
Recommend to read
ALL ABOUT SCREWDRIVERS
Screwdriver is a tool, which, perhaps, to the greatest extent characterizes the "homebrew". Any self-respecting "handy" invent to themselves "personal" screwdriver, unlike any previously...
DESK… ON THE LADDER
Do I need to prove that you can work on ladders will be much easier if the necessary tools will all the Burden be on hand. For example, on the shelf, put on the top arc of the ladder....
