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Durable nylon watch strap threading through spring bars for added security, originally developed for British military use in the 1970s.

NATO straps use thinner fabric with smaller, more rectangular hardware. Zulu straps feature thicker nylon with larger, rounder hardware and typically only one loop instead of two. Both pass under the watch, but Zulu straps are more robust and military-oriented.
Yes, NATO straps work well for diving—they're quick-drying, salt-water resistant, and if a spring bar fails underwater, the watch remains secured by the strap threading under the case. However, rubber or silicone straps are more common for serious diving.
NATO straps are measured by their width (matching your watch's lug width: 18mm, 20mm, 22mm, etc.). Length is typically one-size-fits-all, adjustable via the buckle. Excess strap tucks under the keepers. Measure your lug-to-lug width before ordering.

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