To pull a signal wire into a duct easily with a small force by a method wherein a number of spherical guide members are linked with each other by flexible linear elements in a state that the respective spherical guide members are separated from each other and that postures which enable the signal wire can be inserted freely are maintained.

1st and 2nd hemispherical members 31 and 32 which have piercing holes 21 and 22 are provided. A linking part 23 is provided on the 1st hemispherical member 31 and a linked part 24 is provided in the 2nd hemispherical member 32. The linking part 23 and the linked part 24 are coupled with each other to connect the piercing holes 21 and 22 to each other and a continuous through-hole is formed and, at the same time, a spherical guide member 3 is formed. A number of the spherical guide members 3 are linked with each other by flexible linear elements 4 in a state that the respective spherical guide members 3 are separated from each other and that postures which a signal wire can be inserted freely are maintained. With this constitution, the signal wire 1 can be pulled into a duct easily with a small force and the signal wire 1 is protected from direct contact with the inner surface of the duct.