CPC Subgroup
E04F 17/08 for receiving utility lines, e.g. cables, pipes (covers giving access to the ducts or channels, covers of inspection holes E04F19/08)
Full Title
Vertical ducts; Channels, e.g. for drainage (pipes in general F16L; pipe-line systems F17D ) > for receiving utility lines, e.g. cables, pipes (covers giving access to the ducts or channels, covers of inspection holes E04F19/08)