$fs=1;
difference() {
union() {
    difference() {
    union() {
        translate([-4.45, 0, 3.3 - 1.7]) cube([8.9, 16.1, 1.7]);
        translate([-15.1, 0, 3.3 - 1.7]) cube([30.2, 5.3, 1.7]);
        translate([-7.5/2, 0, 0]) cube([1.2, 16.1, 3.3]);
        translate([7.5/2 - 1.2, 0, 0]) cube([1.2, 16.1, 3.3]);
        translate([-7.5/2, 16.1 - 1.2, 0]) cube([7.5, 1.2, 3.3]);
        translate([-7.5/2, 7.5 - 1.2, 0]) cube([7.5, 1.2, 3.3]);
        translate([0, 3, 1]) rotate([90, 0, 0]) cylinder(h=3, d=7.5);
    }
    translate([0, -0.5, 1]) rotate([-90, 0, 0]) cylinder(h=6.9, d=6.0);
    
    translate([-3, 3, 3.3-1.5]) cube([6, 6.1, 2]);
}
translate([0, 4, 1]) rotate([-90, 0, 0]) cylinder(h=3.3, d=2.7);
}
translate([-4, -0.5, -5]) cube([8, 20, 5.05]);
}
polyhedron(points=[
    [-1.5, 16, 0],
    [-1.5, 21, 0],
    [-1.5, 26, 7],
    [-1.5, 16, 7],
    [1.5, 16, 0],
    [1.5, 21, 0],
    [1.5, 26, 7],
    [1.5, 16, 7]
], faces=[
    [0, 1, 3],
    [3, 1, 2],
    [0, 3, 4],
    [4, 3, 7],
    [3, 2, 7],
    [7, 2, 6],
    [7, 6, 5],
    [7, 5, 4],
    [0, 4, 1],
    [1, 4, 5],
    [1, 5, 2],
    [2, 5, 6]
]);