The NATO watch strap is a single piece of leather that slips between the watch face’s lugs, under the case back, doubling back on itself, and secures by way of a buckle closure. Because of the “caseback double-back,” the watch stays centred and secure on the wrist. Even if one of the lugs were to fail, the watch would remain on the band. The end of the strap is left intentionally long, giving you the ability to fold that back on itself and doubling the band’s on-wrist security.