The Attune Performance Tracking Beads are designed for use with Attune Cytometric Software and Attune NxT Software to automatically characterize, track, and report the performance of the Attune Acoustic Focusing Cytometer and Attune NxT Acoustic Focusing Cytometer daily and over time. Regular calibration of your instrument with these beads will ensure the accuracy and sensitivity of the instrument and allow easy identification of potential shifts or trends in instrument performance. The tracking beads contain distinct sub-populations of beads labeled at different intensities, and are used to establish optimal dynamic range settings for the instrument. The beads are pre-calibrated at the factory and the lot-specific bead performance data captured as a downloadable file for use by the Attune Cytometric/Attune NxT software. Each vial contains enough beads for 50 measurements (Attune) or 25 measurements (Attune NxT). The beads are provided at a concentration of 5 × 10⁶ beads/mL.