The UVP-2688/2788 is 1.85 inch ( 47.0mm) height 8X8 dot matrix display. Single color displays have the choices of three bright colors-AlGaAs red/green/yellow. Multicolor displays are applicable to two bright colors:green and red orange All device have black face and white dot. The AlGaAs red LED chip are made from AlGaAs on a non-transparent GaAs substrate. The green LED chip are made from GaP on a transparent GaP substrate. The yellow and red orange LED chip are made from GaAsP on a transparent GaP substrate.