This comparison is organized within the scope of the Task 1.3 of the EMPIR project MeDDII (Metrology for Drug Delivery). The aim of this task is to validate the developed primary standards for flow rates below 1500 nL/min. This will allow the participating laboratories to test the agreement of their results and uncertainties despite the use of different equipment and calibration methods for the calibration of two different flow meters and a syringe pump. Overall Objective: Using input from A1.3.1 ��� A1.3.4, NEL, IPQ, CETIAT, METAS, RISE, DTI, HS, Bronkhorst, and THL have reported the results from the inter-comparison of the primary standards and improved measurement facilities for flow rates from 5 nL/min to 1500 nL/min (with uncertainty targets of 1 % (k=2) for steady flow and 2 % (k=2) for fast changing flow). NEL acted as the pilot laboratory by analyzing the data and producing the final report. METAS performed the initial and final measurements in this inter-comparison to test the stability of the flow meters over time and IPQ tested the stability of the CETONI Nemesys pump over time. This comparison is organized within the scope of the Task 1.3 of the EMPIR project MeDDII (Metrology for Drug Delivery). The aim of this task is to validate the developed primary standards for flow rates below 1500 nL/min. This will allow the participating laboratories to test the agreement of their results and uncertainties despite the use of different equipment and calibration methods for the calibration of two different flow meters and a syringe pump. Overall Objective: Using input from A1.3.1 ��� A1.3.4, NEL, IPQ, CETIAT, METAS, RISE, DTI, HS, Bronkhorst, and THL have reported the results from the inter-comparison of the primary standards and improved measurement facilities for flow rates from 5 nL/min to 1500 nL/min (with uncertainty targets of 1 % (k=2) for steady flow and 2 % (k=2) for fast changing flow). NEL acted as the pilot laboratory by analyzing the data and producing the final report. METAS performed the initial and final measurements in this inter-comparison to test the stability of the flow meters over time and IPQ tested the stability of the CETONI Nemesys pump over time.