The BD FACSCanto II Flow Cytometer is a multicolor clinical flow cytometry system developed by BD Biosciences for rapid analysis of blood and cellular samples. It uses multiple lasers and fluorescence detectors to identify and quantify different cell populations based on surface antigen expression. The instrument is widely used in hematology, immunology, oncology, and stem cell transplantation laboratories because of its high sensitivity, automation, and reproducibility. In CD34+ enumeration, the BD FACSCanto II plays an important role in identifying and counting hematopoietic stem and progenitor cells expressing the CD34 antigen. CD34+ cell counting is essential for monitoring stem cell mobilization, assessing stem cell harvest quality, and determining suitability for hematopoietic stem cell transplantation. The system commonly uses the modified ISHAGE protocol together with BD Stem Cell Enumeration reagents to provide accurate absolute CD34+ counts and percentages.