I'm guessing so the control arm itself would be a solid 1 piece design instead of multiple pieces welded together. Not sure if they will be lighter due to it being aluminum instead of steel because they do look beefier than the previous one. Looks like a solid piece though, that's for sure. @
racerx1715 your parts are definitely on my WTB list.
Edit** You beat me to it with your explination, lol. I type too slow, haha.