Here are four porcelain insulators for which I've done my best to identify the U-numbers and colors. All are very near mint or better. The R/T Westinghouse is sold. Take the other three for $10 plus postage. From left to right:

U-784 Uneven Mottled Dark Reddish Brown/Black incuse LOCKE/HI TOP/66 mint

U-790 Streaky Brown/Tan incuse THOMAS mint

U-472 Unlisted Radio-treated Chocolate Brown incuse Westinghouse mint - SOLD

U-729 Light Reddish Brown No Name mint