This is a market research request for a highly specific phosphate sensor capable of long-term, deep-water deployment to support harmful algal bloom prediction models. The required instrument must meet exacting technical specifications, including a 6000m depth rating, internal waste storage, and the use of enclosed reagent cartridges. The government intends to purchase one sensor with a cartridge and cable, with delivery required within 30 days after an award. The performance location is the Great Lakes Environmental Research Laboratory. This notice seeks to identify all potential sources, including various business classifications, that can provide a domestically manufactured product meeting the full requirements.