275 cord is half the size and half of the strength of 550 cord (hence being half of 550). 275 refers to the tensile strength of the cord before it will break without using knives, scissors, lighters, etc. 275 cord can be used as an accent on 550 cord bracelets/accessories, and also used as the main cord in making miniature versions of my work. I have loved making Mommy and Me/Daddy and Me sets with matching 275 cord. It is extremely durable and easy to keep on your person should you need it. I pride myself on making functional accessories that just so happen to be pretty as well.