Re: 48cc vs. 69cc.
There are two different types of conduit 'straps'. One is for 'EMT' conduit which is super thin and the other style is for 'IMC' conduit which is much thicker (and so are the straps). The thicker or stronger conduit hangers or 'straps' will also be marked "rigid" and have red writing on the bags. They're sometimes found in the plumbing section at Home Depots or Lowes.