The Sony A7s Cage from SmallRig is one of the cheapest cages on the market. Ihis camera cage is made of aluminum alloy material, only 180g. The cage lightweight and solid, easy to carry it. If you’re on a tight 
budget and just want a basic cage for your A7S, this is the right option for you.
The camera cage provided two mounting holes for attaching short 1/4” rod to the bottom plate. The Sonly A7s Camera Cage reposition the two mounting holes, so you don’t have to remove your camera when attaching the short rod, which saves time on assembling.
The SmallRig Sony A7s Cage features 1/4”-20 mounting holes for attaching accessories and mounting onto a tripod plate.
The DLSR Cage also can be directly attached to a Manfrotoo quick release plate with two 1/4” screws.