Seiko 5 Military SNK805K2-var-NATOS18 Automatic Nylon Strap Men's Watch Suitable for any kind of field work with or without machineries to operate - light or heavy - the nylon and cloth built NATO strap is more breathable than any other type for your skin. It’s tightly-woven to add for durability, comfort and a better grip. Its flatness is also better than ordinary nylon and flexes easier right from the first wear.