High precision, portable surface roughness testers with a dedicated control unit equipped with analysis functionality rivalling that of benchtop surface roughness testers, complying with the latest international standards applying to surface roughness measurement. The color-graphic LCD has excellent visibility for displaying calculated results and assessed profiles. This is useful for checking results without printing them out. A backlight improves usability in dimly lit environments. The built-in high quality, high-speed thermal printer provides hardcopy of measurement results when required including BAC and ADC curves in landscape format, just as they appear on the screen. The choice of models provides a measurement range of 25mm or 50mm. Password protection for setups is available for preventing accidental changes to settings. A manual adjustment knob enables fine positioning of a small stylus for positioning, which is useful when testing the inside surface of small holes. The instrument can be used stand-alone or mounted on a user-supplied stand. Many optional accessories are available to extend the application range.