ez way to find out is goto autoparts website and type hummer 3 "part", like "brakes". get part #,then type in the same for blazer. if the #s are the same,well you got it..
?why not just buy h3 parts? or do you have blazer parts?

 

sir. i don't have H3 or Blazer now but i am thinking to own ( 2006 / 2009 ) H3 if it's the same blazer parts because i live in small town and we have small replace autos parts not a dealership center

 

A Colorado will match up a lot more then the blazer.

 

26.5 Blazer parts fits on the H3.

It is like ordering parts for any GM vehicle. Since you get the internet, you can order any part you are likely to need.