Magnetic disk drive

摘要

A box body 10 forming part of an HDD 1 has a top cover 12. The top cover 12 includes a breathing hole 20 drilled therein. The breathing hole 20 serves to eliminate any pressure difference between an inside and an outside of the HDD 1. A fiber waterproof body 30, which includes a waterproof fiber material 32 or the like, is fitted in a large-diameter hole 21 of the breathing hole 20. A pore waterproof body 40, formed by bundling up an infinite number of slender pores 42A, is mounted in a small-diameter hole 22 of the breathing hole 20.