A hermetically resealable hard-disk drive (HDD) configured for recharging with a low-density gas. The hermetically resealable HDD includes a disk enclosure (DE), a magnetic-recording disk, a head-slider, an actuator, a low-density gas, a through-hole, and a plug. The DE includes a base, and a first cover and a second cover joined to the base. The second cover is disposed above the first cover. The through-hole is configurable for injection of a low-density gas into the DE. The low-density gas, having a density less than air, substantially fills the DE. The plug is press-fitted into, and hermetically seals, the through-hole. The plug is removable to allow recharging the DE with the low-density gas; and, the through-hole is configured to accept a resealing plug to be press-fit into, and to reseal hermetically, the through-hole after recharging. A method for injecting low-density gas into, and sealing, the hermetically resealable HDD is also provided.