Here is a heavy duty radio strain insulator that I have added to my collection. It is made by Pyrex, measures 14-inches end to end, weighs about 9 pounds, the glass is clear even though the picture looks kind of a straw color. The glass appears to be hollow in the middle. I have a catalog print out from 1928 that shows this thing sold for about $18.50.........I paid a whole lot more than that for it! But it is a neat addition to my Pyrex collection.