difference(){
union(){
    cube ([10,50,10]);
translate([0,100,-25]) cube ([10,20,35]);
color([0.5,0,0])translate([-3,0,0])cube([3,120,10]);
color([0.5,0,0])translate([10,0,0])cube([3,120,10]);
}
translate([0,30,5])rotate([0,90,0])cylinder(h=30,r=2.2, $fn=20, center=true);
}
