Tire pressure monitoring system

According to the invention, there is provided a tire pressure monitoring apparatus comprising: a body comprising an enclosed internal volume; mounting means for mounting the apparatus to a tire valve, the mounting means comprising means for opening the tire valve to allow gaseous communication between the internal volume of the tire and the internal volume of the body; a valve in gaseous communication with the internal volume of the body for receiving a tire inflation device to allow inflation of the tire via the apparatus; and an enclosed pressure chamber, in gaseous communication with the mounting means for receiving the internal pressure of a tire to which the apparatus is mounted, the chamber housing at least: a power source; a pressure sensor; and an antenna for emitting a signal indicative of a pressure within the chamber, wherein the power source, pressure sensor and antenna are at least partially encased in a binding material to maintain their relative positions in the pressure chamber.