The 102GS has the same rim as the 102G, but with a shallower cup. It is like a Bach 5GS but with a larger inner diameter, or a Bach 4G with a 5GS cup depth.
The 102GS is a great choice for players who like the Bach 5GS, but need a bit more room. It is also great for players who like the Bach 4G or Wick 4AL, but who want a shallower cup for a more brilliant sound and easier upper register.
The 102GS has an ID of 1.02 inches and a .280 throat.