As you know, A&A MFG is one of the largest pop up head manufactures in the world and they are always looking to innovate their product lines. The style 2 pop up head is a dated head that was used in a lot of new pool construction.
Over the years, A&A has steered away from the "Style" line and moved to something they refer to as "Gamma". The Gamma Series are awesome heads. There is no more such thing as high flow vs. low flow. These heads are completely adjustable and they are also reinforced and built to last a lot longer.
So what A&A has done is make a retro head called the Gamma 2 to fit into the Style 2 collar. However, these are limited to White, Black, and Gray heads. So if you have a Style 2 head, we strongly recommend getting a Gamma head so your pool can work more efficiently and have a pop up head to last through the years.