cl1 = 0.4;
cl2 = 4.0;
Point(1) = {0, 0, 0, cl2};
Point(2) = {8, 0, 0, cl2};
Point(3) = {8, 2, 0, cl2};
Point(4) = {0, 2, 0, cl2};
Point(5) = {2.5, 2.2, 0, cl1};
Point(6) = {5.5, 2.2, 0, cl1};
Point(7) = {5.5, 5.2, 0, cl1};
Point(8) = {2.5, 5.2, 0, cl1};
Line(1) = {1, 2};
Line(2) = {2, 3};
Line(3) = {3, 4};
Line(4) = {4, 1};
Line(5) = {5, 6};
Line(6) = {6, 7};
Line(7) = {7, 8};
Line(8) = {8, 5};
Line Loop(9) = {5, 6, 7, 8};
Plane Surface(10) = {9};
Line Loop(11) = {1, 2, 3, 4};
Plane Surface(12) = {11};
Physical Surface(13) = {10};
Physical Surface(14) = {12};
Physical Line(15) = {5};
Physical Line(16) = {3};
