I used them when they first came on the market, had the (gs) stamped on the base,I think they were made with a two part core. The rear section was hard and the front was much softer. Speer claimed they were poured in the jacket molten ( I think) so the sections wouldn't seperate at impact. I don't know how they are constructed now as I don't have a need for the premium bullets, Whitetails aren't that tough. It was an effort to take away coustomers from Nosler.