Since the proximal end portion 31 b of the distal end side coil 31 and the distal end portion 32 a of the proximal end side coil 32 are not entangled with each other, the coil fixing member 4 is a member which fixes the proximal end portion 31 b of the distal end side coil 31 and the distal end portion 32 a of the proximal end side coil 32 to the core member 2.