Product Features Large, 6.5-inch LCD screen Pupil diameter measurement Wider range motorized chin rest movement Residual astigmatism indication (K-model) Test time is screening mode 49 seconds per eye Employs accommodative micro fluctuation with high pass frequency 1-23 Hz. SPEEDY-i Auto Refractometer/Keratometer Now With A Revolutionary Accommodative Testing Feature Patients commonly complain of asthenopia, but until now, there was no easy or reliable way to test for dynamic accommodative lag. With the new Speedy i/k, accommodative accuracy is measured with a novel methodology that allows you to understand the source of your patient symptoms, as well as quantitatively adjust your prescription.