Patent ID: 7021153

Claim:
A measuring device ( 1 ; 21 ; 33 ) for controlling an installation torque of a fastening element ( 4 ; 32 ) and securable to engagement means ( 3 ; 35 ) of the fastening element ( 4 ; 32 ), the measuring device ( 1 ; 21 ; 33 ) comprising indicator means ( 5 ; 24 ) for a visual display of the installation torque; a plurality of microcapsules filled with a dispersible color dye and supported on the indicator means ( 5 ; 24 ); at least partially transparent covering ( 7 . 1 ; 7 . 2 ; 22 ) provided on an outer surface of the indicator means ( 5 ; 24 ) the indicator means ( 5 , 24 ) being visible through a transparent region of the covering; and an opening ( 27 ) through which a fastening element ( 4 ; 32 ) can extend.