The National Institutes of Health (NIH) seeks a firm-fixed-price purchase order for maintenance and repair services for an Orbitrap Eclipse Mass Spectrometer and associated equipment used by the National Institute on Aging (NIA) in Bethesda, Maryland. The contractor must provide OEM-certified parts, software upgrades, and technicians, with a 24-hour repair request acknowledgment and a 72-hour onsite visit requirement. The base period of performance runs from June 1, 2026, to May 30, 2027, with two optional one-year extensions. Services will be performed at 9000 Rockville Pike, Bethesda, MD 20892. No specific budget amount is provided in the description.