This is an original 150B dial plate (or porcelain) that has had a dial overlay applied. This dial will fit a #5, #4, and #2 dial (but not a #6 dial). The original 150B plates with the Z over the 0 are so hard to find in excellent condition these days. This is a great and inexpensive solution to the problem. It is indistinguishable to the original product once installed. Satisfaction is guaranteed!