difference() {
    hull() {
        cylinder(30, 15, 15, $fn = 500);

        translate([-12.5, 13.5, 0])
        cube([25, 2, 30]);
    }
    translate([0, 0, 2])
    cylinder(30, 13.5, 13.5, $fn = 500);

    translate([-1.25, -15, -1])
    cube([2.5, 15, 32]);

    translate([0, 0, -2])
    cylinder(10, 6, 6, $fn = 500);
}