here is "mobile's" RS roll cage mount.
it's a clamp type for a little more security.
Quote:
It's from MANFROTTO. It contains the "035 SUPER CLAMP" and the "486 COMPACT BALL HEAD". The Super Clamp is a universal clamp, which fits for different cages. Very stable.(To combine both you need an adapter - MA 037 - from 3/8" to 1/4")



mobile's camera mount LINK