Pneumatic Fan Clutch Wrench Set

fan clutch
A fan clutch is a thermostatic device that exists as an integral component of certain automotive cooling systems.
A Viscous (fluid) drive coupling device connected to the center of the fan to permit variable engine fan speeds in relation to engine speeds. The Clutch engages and disengages the fan according to the engine temperature through a thermostat
A viscous-fluid clutch that controls how fast an engine fan rotates to help cool an engine.

pneumatic
of or relating to or using air (or a similar gas); "pneumatic drill"; "pneumatic tire"
(pneumatically) in a pneumatic manner; "at the present time the transmission is very often done hydraulically or pneumatically"
(pneumatics) the branch of mechanics that deals with the mechanical properties of gases
An item of pneumatic equipment

wrench
a sharp strain on muscles or ligaments; "the wrench to his knee occurred as he fell"; "he was sidelined with a hamstring pull"
make a sudden twisting motion
Injure (a part of the body) as a result of a sudden twisting movement
Turn (something, esp. a nut or bolt) with a wrench
twist or pull violently or suddenly, especially so as to remove (something) from that to which it is attached or from where it originates; "wrench a window off its hinges"; "wrench oneself free from somebody's grip"; "a deep sigh was wrenched from his chest"
Pull or twist (someone or something) suddenly and violently

set
a group of things of the same kind that belong together and are so used; "a set of books"; "a set of golf clubs"; "a set of teeth"
A collection of implements, containers, or other objects customarily used together for a specific purpose
put: put into a certain place or abstract location; "Put your things here"; "Set the tray down"; "Set the dogs on the scent of the missing children"; "Place emphasis on a certain point"
A group or collection of things that belong together, resemble one another, or are usually found together
A group of people with common interests or occupations or of similar social status
fit(p): (usually followed by `to' or `for') on the point of or strongly disposed; "in no fit state to continue"; "fit to drop"; "laughing fit to burst"; "she was fit to scream"; "primed for a fight"; "we are set to go at any time"