Abstract: An adaptor for fitting a small diameter wiper arm pin to a large diameter hole in a wiper superstructure comprises at least one element of which the inner surface defines a cavity to receive the small diameter pin. The outer surface of the pin adaptor defines an outside diameter which exceeds the diameter of the pin and is adapted to fit the large diameter hole. Preferably, a pair of complementary elements are provided to encase the pin and the outer surface further defines a groove to receive a leaf spring of a conventional wiper connector assembly. An aligning flange cooperable with a slot in the wiper assures correct alignment of the adaptor in the superstructure.