Race belts are great for triathlon or road / trail running.  
 
The race belt is a basic but essential piece of equipment for triathletes.  Used in "T2", the second transition in a triathlon, from bike to run, the athlete has the race number ready on the belt so that the number can be installed at the waist quickly and efficiently.  Saving time!  
 
It's also great for runners who don't like puting pins through thier t-shirts or singlets.  
 
(3) possibe fixed attachment points 4.5" or 9" spacing. 
Works for most race numbers 
Adjustable waist belt 
Unstreatched max - 33" (will streatch much larger)
Unstreached Min 26"
Fits most adults and youth