Only half of all wall outlets need the ground prong: https://www.thiings.co/things/wall-outlet
And this decidedly is not a square not: https://www.thiings.co/things/square-knot
And this decidedly is not a square not: https://www.thiings.co/things/square-knot
Though I don't know if that applies to the region that has the D: face sockets.