An air bag apparatus for a compact vehicle, having an air bag that is capable of restraining an operator on a seat from a front direction, in response to an expansion of the air bag, wherein it is possible to securely restrain the operator on the seat without a need for enlarging the expansion volume of the air bag, even if a yaw behavior andor a rolling behavior of the vehicle body areis large. Specifically, the present invention provides transgenic mice comprising mutations in a ROR gene. The composition is characterized as having a bimodal molecular weight distribution, and a ductile-brittle transition temperature, Tdb, of less than \u221220\xb0 C. The upper antenna element is electrically connected to the ground plane and to an antenna feed element.