Abstract: A pulling device transmission includes an stepless V-belt connection two pulleys wherein at least one of the pulleys is an adjusting pulley which is composed by two halves between which the belt runs through. The operative diameter of the adjusting pulley is adjustable relative to the belt plane where the belt runs thereon and the adjusting pulley halves are symmetrically pre-stressed with respect to the belt plane. A variator unit is designed for displacing the travel path of the belt in the respective to the adjusting pulley.