Refer to the following for the SY series manifold blanking plate assembly model:
The VHK series catalog can be found here.
The VHK series catalog can be found here.
The VQ7-6/VQ7-8 series catalog can be found here.
Further details can be found here.
Though it depends on the usage, stopping for a few tens of seconds should not cause the stop position to shift much, but holding the position for a long period of time is not possible.