Any subcontractor, material supplier, or laborer who is performing or has performed labor or work or is furnishing or has furnished material for any public improvement provided for in a contract between the public authority and a principal contractor, and under a contract between the subcontractor, material supplier, or laborer and a principal contractor or subcontractor, at any time, not to exceed one hundred twenty days from the performance of the last labor or work or furnishing of the last material, may serve the public authority an affidavit stating the amount due and unpaid for the labor and work performed and material furnished, when the last of the labor or work was performed and when the last of the material was furnished with all credits and setoffs thereon, and the post-office address of the claimant. If a claimant serves an affidavit under this section, the claimant shall serve the affidavit to the representative of the public authority named in the notice of commencement.
One or more laborers may authorize an agent to prepare, execute, file, and serve the affidavit required by this section. The affidavit may set forth the claims of one or more laborers, provided that the affidavit separately itemizes the claim of each laborer and may set forth claims for wages that are contractually due but are unpaid.