These are the newest set of Caesar Miniatures Modern US Army, 1/72nd scale.
They are current US Army troops for the War in Afghanistan.
These new sets only have about 21 figures in them and they seem to be retailing for about $12 each, so the price per figure is expensive.
The individual figures are very nice, as you can see there the poses are very good.
The troops come with a separate back pack, CamelBak item, in several configurations. They go into a hole in the back of the figures. They fit perfectly. I tried to maximize the variety of the figures, giving them as many different backpacks per pose as I was able to give.