Here's an embossing that makes an otherwise common insulator quite rare: HEMINGRAY (over) MADE IN U.S.A.. The letters M& I are connected by raised glass. Reverse has 'No 40' The dome top is also too big as its from a Hemi #42 - not the slimmer No 40 style. No dome number. This insulator is very near mint - I count only three partially nicked drips. That's it. A real oddball - when have you seen another? $20 plus $5 shipping gets it.