To make the contact part or the tire back corner part in a cross chain a small diameter by providing a cross chain formed by a main part and the contact part of the back corner part of a tire, anti making the diameter of the chain link of the contact part off the back corner part of the tire smaller titan the diameter of the chain link of the principal part.

A cross chain 6 is formed by a main part 7 and a contact part 8 of the back corner part of tire. tire main part 7 has its one end connected to a surface side chain 3 through a connector 71. The diameter of a chain link 82 of the contact? part 8 of the back corner part, or the tire is made smaller than the diameter of a chain link 72 of the main part 7. Thus, the thickness of the contact part 8 of the back corner part of the tire can be made smaller than the thickness of the main part. 7 without reducing the diameter or the chain link 72 of the main part 7. That is while he snow performance and durability are kept, the contact part 8 of the back corner part of the tire in the cross chain 6 can be made with a small diameter.