The National Institute of Standards and Technology (NIST) is conducting market research to identify sources for a fiber-coupled widely tunable diode laser system for interferometric displacement measurement in mass and force metrology. The system must meet essential technical specifications, including a wavelength tuning range of at least 160 nm covering 1550 nm, wavelength accuracy under 2 pm, and output power of 10 milliwatts at 1550 nm. No specific budget amount or performance location is mentioned in the notice. Respondents are asked to submit capability information as soon as possible, preferably before the notice’s closing date, with responses limited to 10 pages. This is a sources sought notice only, not a solicitation, and does not obligate the government to award a contract.