Determination of a fast route from a source node to many destination nodes. The receptacles include an open upper end with a D-shaped configuration and a closed bottom end with a substantially circular bottom configuration. Further, the transfer case includes a disconnect clutch and a disconnect shift mechanism to establish a two-wheel drive mode in addition to the four-wheel drive modes. 6-mm thick thin-walled regions on the face side of the crown portion and the face side of the side portion, a medium-thick-walled region thicker than the thin-walled region of the crown portion at the back of the thin-walled region, and a high-rigidity region on the face side of the sole portion.