Most address labels are a bright white color with black text printed on them. These serve the purpose they’re made for, but if you use colored envelopes, there is a label from Dymo that actually blends in with the envelope color.
Dymo Clear Address Labels (30254) are made from an opaque plastic material which when placed on a colored envelope (or other surface) will show the color of the surface through the label. The print/text on the labels will be black, so it is advised to use these labels on a light colored envelope. These look so much better than a white label on a colored envelope. See the entire range of Dymo Address Labels here.