We noticed that our nebulizer needle (G1946-67098) is flush with the end of the nozzle. The Agilent "Nebulizer Adjustment Fixture" User Guide recommends a protruding distance of 0.003 inches (0.08 mm) for ESI. We plan to run an experiment testing different distances but are curious about other people's results and how this has affected sensitivity, reproducibility, and/or ionization efficiency.