#declare monitor_stand =
difference {
  union {
    box { <0.2,1.9,0.2> <11.8,2,11.8> }
    difference {
      cylinder { <0.2,1.8,0.2> <11.8,1.8,0.2> 0.2 }
      cylinder { <0,1.8,0.2> <12,1.8,0.2> 0.1 }
      box { <0.2,1.8,0.1> <11.8,1.5,0.5> }
      box { <0,1.9,0.2> <12,1.5,0.5> }
    }
    box { <0.2,1.60,0> <11.8,1.8,0.1> }

    box { <0,0.2,0.2> <0.1,1.8,11.8> }
    difference {
      cylinder { <0.2,1.8,0.2> <0.2,1.8,11.8> 0.2 }
      cylinder { <0.2,1.8,0> <0.2,1.8,12> 0.1 }
      box { <0.1,1.8,0> <0.5,1.5,12> }
      box { <0.2,1.9,0> <0.5,1.5,12> }
    }
    box { <12,0.2,0.2> <11.9,1.8,11.8> }
    difference {
      cylinder { <11.8,1.8,0.2> <11.8,1.8,11.8> 0.2 }
      cylinder { <11.8,1.8,0> <11.8,1.8,12> 0.1 }
      box { <11.9,1.8,0> <11.5,1.5,12> }
      box { <11.8,1.9,0> <11.5,1.5,12> }
    }

    box { <0.2,0,0.2> <0.6,0.1,11.8> }
    difference {
      cylinder { <0.2,0.2,0.2> <0.2,0.2,11.8> 0.2 }
      cylinder { <0.2,0.2,0> <0.2,0.2,12> 0.1 }
      box { <0.1,0.2,0> <0.5,0.5,12> }
      box { <0.2,0.1,0> <0.5,0.5,12> }
    }
    box { <11.8,0,0.2> <11.4,0.1,11.8> }
    difference {
      cylinder { <11.8,0.2,0.2> <11.8,0.2,11.8> 0.2 }
      cylinder { <11.8,0.2,0> <11.8,0.2,12> 0.1 }
      box { <11.9,0.2,0> <11.5,0.5,12> }
      box { <11.8,0.1,0> <11.5,0.5,12> }
    }
  }
  cylinder { <0.5,1.5,0.5> <0.5,2.5,0.5> 0.2 }
  cylinder { <11.5,1.5,0.5> <11.5,2.5,0.5> 0.2 }
  cylinder { <0.5,1.5,11.5> <0.5,2.5,11.5> 0.2 }
  cylinder { <11.5,1.5,11.5> <11.5,2.5,11.5> 0.2 }
}