The Marvel II AB-Scan with UBM is a high-resolution ophthalmic ultrasound device by Appasamy, combining A-Scan (axial length measurement), B-Scan (detailed cross-section), and Ultrasound Biomicroscopy (UBM, ultra-high frequency for anterior segment detail) to provide exceptional imaging for both front and back of the eye, aiding diagnosis for cataracts, tumors, trauma, and IOL planning with advanced features like artifact reduction and clear imaging.