Section 573.7 - Claims for material or labor1. Any person, firm, or corporation who has, under a contract with the principal contractor or with subcontractors, performed labor, or furnished material, service, or transportation, in the construction of a public improvement, may file, with the officer, board, or commission authorized by law to let contracts for such improvement, an itemized, sworn, written statement of the claim for such labor, or material, service, or transportation.2. A person furnishing only materials to a subcontractor who is furnishing only materials is not entitled to a claim against the retainage or bond under this chapter and is not an obligee or person protected under the bond pursuant to section 573.6.C97, §3102; S13, §1989-a57; C24, 27, 31, 35, 39, §10305; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §573.783 Acts, ch 55, §1