Abstract: A reflection road stud comprising a body member attached or attachable to a road surface without excavation thereof, a reflector assembly mounted in or integral with the body member and comprising at least one reflex reflecting surface, means for wiping the reflecting surface when a road wheel of a vehicle passes over the road stud, and a region of resilient deformability disposed between the reflector assembly and the road surface when the road stud is attached thereto, whereby, when a road wheel of a vehicle passes over the road stud the reflector assembly is depressed towards the road surface and returns substantially to its initial position when the depressing force of the road wheel is removed.

Abstract: A tire has a succession of peripherally arranged compartments. The compartments are interconnected by separate passages via one-way check valves for inflating the compartments through one passage and deflating them through another. The passages are both connected to a main valve which enables the passages and thereby the compartments to intercommunicate at least during inflation or deflation but separates the passages and thereby the compartments otherwise.