Abstract: A snow plow assembly with a longitudinally extending plow body has a blade mounting structure that supports a longitudinally extending plow blade. The blade mounting structure has a series of hinges that receive a longitudinally extending pivot rod to couple the plow body to the snow blade and set of springs to bias the snow plow blade into an operative position and to resiliently restore the snow plow blade to the operative position after encountering an obstacle. The hinge portions fixed to the snow plow body each have a receiving slot to slidingly receive a hinge key and the hinge keys define a bearing surface for abutting one end of the coil spring. A locating notch is provided in the hinge keys to limit relative movement between a hinge key an associated hinge portion. A hinge lock to capture the pivot rod is also provided.