The 4-5/16" (110 mm) front brake disc for Coleman AT125-EX and AT125-UT ATVs is commonly called a rotor. Our replacement steel front brake disc is the same as the one on a brand-new AT125-EX/AT125-UT straight from the Coleman factory. This brake rotor for Coleman AT125-EX and AT125-UT ATVs uses four 1/4" (6.52 mm) mounting holes.