Here's a tough U-638 NN Thomas with the "blue jean" stitching in the cable groove. Apart from the surface dust seen in the photo this beauty is easily VNM with only a teeny glaze flake underneath upper wire groove and 2 small wire rub marks (about the size of basmatti rice. Other white areas showing in wire groove appear to be glazed and were made that way at the factory.

First email gets this tough early porcelain insulator for the sale price of only $15 plus shipping. Thanks