In HDR brachytherapy, every millimeter matters. Accurate measurement of needle protrusion is essential for correct dwell-position planning, which directly impacts both treatment effectiveness and patient safety. The Precise BRT Needle Measuring Device was designed to eliminate the challenges associated with traditional metal rulers: awkward body positioning, poor visibility, risk of misreading densely placed needles, and difficulty maintaining a stable measurement. With a refined mechanical design, a certified millimeter scale, and intuitive operation, this device enables fast, reliable, and repeatable measurements, improving workflow and reducing clinical risk.