Nice Embossed marked mine insulator. The patent info can be found on NIA website. Charles K. King of Mansfield Ohio. Feb 12, 1901. Acquired via eBay from Pennsylvania area. Too Bad the T in PAT has a chip, but it is still there, hanging like a champ. Not bad for 100 years. Would be nice to have the related hardware. 2-1/2 inches tall and 2-3/8 inches diameter. Hole is a tight 5/8 inch diameter.