This is a cast iron pin designed for a mine insulator and to be driven into the mine wall. It bears the PAT Dec 8-08. Note the threaded area is split and has some felt like material in the division. The smaller of the two white porcelain mines is a U-90. It is marked Thomas and is in good condition. The larger white porcelain mine is also in good condition ; however, it has has about five marks into the porcelain glaze, I would presume that most are from firing. There is one near the wire groove that might be wear. All three pieces for $75 shipped within the continental US. Personal check is preferred or PayPal without fee to Seller. I will be posting more items so check ICON often. Jim White Indianapolis