To provide: a fiber having excellent adhesiveness, which is able to be bonded to a polar resin, a resin containing an inorganic filler, a ceramic, glass, a metal or the like, without being subjected to a primer treatment or the like; and a nonwoven fabric. The present invention offers a reduction in signal delay. The tip body proximal end is engageable with the distal end of the sheath member distal end. Secondary TMS electromagnets may be fired at a fraction of the power used to energize the primary TMS electromagnet to shape the resulting magnetic field.