This is a very convenient automatic dustpan, normally located in the plinth of a kitchen unit. It is for sweeping up crumbs from the floor in an area which gets a lot of use and may need more cleaning than would warrent your one-a-week vacuum!
No need to bend down with a dustpan and brush - no piles of dirt swept into the corner to be sucked up in the weekly vacuum and no worries going bare-foot!
Please also ensure that you either order a dedicated VacPan kit (2150) in the Inlet kit and Fittings section, or at the very least, a sharp 90°bend (2007), a Sweep Tee (2008), and some flexible vacuum pipe (2021) which comes with a pair of jubilee clips to attach to ridgid vacuum pipe. You may have low voltage wire and pipe left over from the rest of your installation.
For instructions on how to install please see the picture above or look on page 8 of the Design Installation Manual PDF document shown below.