NGC 1964 Kennedy half transitional off-metal struck on a clad quarter planchet. The coin is a rare transitional off-metal, being not only on a quarter planchet, but also on a clad quarter planchet. For the year 1964, quarter planchets were made of silver, but this coin is struck on the next year's quarter planchet, 1965, which is the year quarters officially were struck in clad metal.
Transitional off-metals are one of the rarest error types because they are so unlikely to occur. There are few known clad 1964 Kennedy halves, and perhaps there are around 10 or so known. This is one of the higher grade examples you will find. A popular error type!
MS64 flashy surfaces and exceptionally nice for the grade.