NOAA intends to negotiate a sole-source contract with YSI Inc. for custom Nile water level sensors and associated cables as spare parts for its environmental monitoring stations. The sensors are required by the National Ocean Service Engineering Division in Chesapeake, VA, which supports monitoring stations across U.S. coasts, Great Lakes, Caribbean, and Alaska. YSI/Xylem is the sole manufacturer and distributor, and the equipment is already integrated into NOAA's standard systems, with existing training, calibration, and repair capabilities. Using alternative components would incur additional costs, delays, and require extensive testing and system integration. Interested firms that believe they can fully meet the requirements may submit substantiating documentation to the contract specialist.