You have 2 adjusters, and one white holder that is not an adj. The plastic blue, or white is what holds the headlight in. In the center is a metal shaft, might have a red piece of shrink tube on it( throw it away, I put it there so they couldn't scratch another light. The end of the metal shaft sticking out the rear is the adjuster. Turning it will move the angle of the light up/dn, lft/rt Most people use pliers to turn it. Hold the plastic so it doesn't turn, and turn the metal shaft. I think it's 1/8".