The Frame Container ROP contains a subnet of ROPs and makes them dependent on all of its inputs, without passing on any frame dependency changes caused by a Batch ROP or Frame Dependency ROP to those inputs. All contained nodes are made implicitly dependent on all inputs to this node.
For example, if it contained a Batch ROP with a mantra1 ROP as an input, it would run mantra1 in a batch (say frames 1-240). If the frame container ROP had mantra2 as its input, the batch frame range would not affect it, and instead the frame range that the frame container is being evaluated at would be used. Without the frame container, with mantra2 as an input to mantra1 instead, mantra2 would be evaluated in the same batch of frames, 1-240.