... Screen(2-32 points) 1. drag, draw-line, rotate, zoom in/out 2.Withstands severe environments 3.Stable, no-drif 2,4,6,10,16 ... force is requiredMinimum Touch Object2.5 mm X 2.5 mmVandal-proofNo break by 1-pound steel ball dropping from 130 cm ... SystemOperation System Linux/ Dos / Windows 7/XP//Mac OS 2,4,6,10,16,32 points 32/42/52/55/65 inch ...