The urethane flat belts were derived from the gravity roller brakers manufactured by DuraBelt. It is applicable on roller blakes used to decline roller conveyors. The braking force can be adjusted by varying the number, width, tension and pattern of the belts. Flat belts have a slight resistance to bending but the primary source of braking is the nature of rollers themselves. The axis of a roller is not precise at the center of rotation, The TIR of the unit is always at zero. The rollers have high and low points that are almost always out of phase with its neighbor that links them together. The unit produces a resistance to movement, wherein the belt is forced to stretch and relax with each rotation. In a way, the exact dimensions of the beltse are hard to determine.