Modern banjos have standard head sizes. Vintage banjos on the other hand have head sizes that are all over the map. At Deering we use two different head diameters. The most common is an 11" diameter head. When the Goodtime Americana came out, Deering started offering banjos with wider 12" diameter heads. Deering now offers a number of different models that come with a 12" diameter head.
Models that take a 12" diameter head are as follows:
The other question you must know about your banjo head is the crown height. Here is a breakdown of the crown heights used on all Deering made banjos.
To find out the how to know what year your Deering upperline or Deering made Vega banjo was made, go here.