Mechanics lien and notice requirements can be tricky, and when document names don't seem to match up it can definitely be confusing.
In Nevada, there are different notices that may be required. All parties other than those who have contracted directly with the property owner (or a wage laborer) must provide a notice of right to lien to the property owner within 31 days of first furnishing labor and/or materials. The notice must also be provided to the prime contractor.
Further, an additional notice is required for residential projects. For residential projects, a lien claimant must serve the property owner and the prime contractor a 15-day notice of intent to lien at least 15 days prior to recording the lien itself.
Finally, while a prime contractor is generally not required to send preliminary notice, they may be assessed a penalty by the State Contractors Board if they do not deliver a copy of the lien information notice to property owners and each subcontractor on a project. This notice, set forth by NRS Section 108.246, is incorporated into the contracts of many contractors so it doesn't require a separate mailing.
In the zlien system specifically, the notice of right to lien is entitled: "31-Day Preliminary Notice of Right to Lien" and the words "Notice of Right to Lien" appear as the title on the document itself. The information notice required from the GC is entitled: "NRS 108.246 Notice to Owner and/or Subcontractor."