Securely hold an orifice plate in the line to ensure differential pressure measurement in accordance with AGA 3, API 14.3, and OIML 5167. This low-maintenance flow measurement device simplifies the plate inspection and removal process with one tool required for flange separation. Rigorous manufacturing procedures, including correct alignment of the flange bore and plate centering, ensure every Daniel flange union meets strict AGA tolerances for reliable, long-term measurement performance. The device is available in a range of standard line sizes and configurations with optional materials available upon request to meet more severe application requirements.