10 Black & 10 Orange. These Whistle Buckles are great for emergencies. A must-have for any outdoor enthusiast. In an emergency situation, the whistle can be used to attract attention and to help guide rescuers.  The bright orange color allows the buckle to be seen easier in dim light conditions. Great for hunters. Goes well with orange paracord bracelets.They're contoured and they're non-adjusting, meaning that each buckle end has only one opening. These two features together, plus the fact that they're smaller than most other whistle buckles, make them perfect for paracord bracelets. They can also be used to replace conventional buckles on rucksacks, life-vests, etc, for an added safety feature. These buckles have 1/2" (13mm) openings for nylon, plastic or cotton straps. They can only be used for applications where webbing doesn't have to be adjusted.