Model U28R550UQP , 28" , 4K , Panel IPS , Resolution 3840x2160 , Form factor 16:9 , Refresh rate 60 Hz , Brightness 300 , Contrast 1000:1 , Dynamic contrast (DCR) Mega Contrast , Response time 4 ms , Horizontal 178 degrees , Vertical 178 degrees , 2xHDMI , 1xDisplayPort , 1xAudio-Out , Tilt , 75 mm x 75 mm