To satisfy adjusting regulation conditions simply and efficiently with no dispersion by forming a display section with a normal region, attention regions and danger regions, and applying different colors to these regions.

A display section 11 is provided at the tip section of a monitor pin 10, and the display section 11 is formed with a blue ring B, yellow rings Y provided on both sides of the blue ring B, and red rings R provided on both sides of the yellow rings Y. The blue ring B indicates a normal region, the yellow rings Y indicate attention regions, and the red rings R indicate danger regions respectively. A coil spring is used as a spring member 9, and the elastic coefficient of the spring member 9 is set to a prescribed value in advance so that the tensile force of a main cable 2 becomes 100 kgf when a brake lever 1 is pulled up with the force of 20 kgf and a lever pawl piece 1a is moved from the original position of a ratchet section 4 by 8 notches.