yeah, called an 8 point socket

sears



wrote:
on the Yank side of the pond, we have plumbing drain plugs which have a
male, square grasping surface. The 12-point machine-screw/bolt sockets
we americans have around, will not grab onto these square tails.

Does anyone make purpose-built, properly-sized female-square socket
drives for rotating these plumbing items when the clearance around them
is too small to allow a wrench?