The red and green striped insulators shown here have either been heat stained or painted, the colors are too "strong" and appear to have been aplied over the origihal white (clear) glaze. On the real ones, the glaze is applied over the color stripes, and the surface reflectivity should more even over both the white and colored portions.
No 2UM porcelain insulators were ever produced with a green stripe.
The correct colors and appearance can be seen on these examples of other "stripers". [id=269697825]