$fn=60;

include <BOSL2/std.scad>

union() {
    zcyl(d=75, l=3);
    cuboid([37.5,37.5,3], rounding=5, edges=[FRONT+LEFT], anchor=BACK+RIGHT);
}
zcyl(d=20, l=25, anchor=BOT);
difference() {
    union() {
        tube(od=75, wall=3, l=25, anchor=BOT);
        rect_tube(size=37.5, h=25, wall=3, rounding=5, edges=[FRONT+LEFT], anchor=BOT+RIGHT+BACK);
    }
    cuboid([34.5,34.5,25], rounding=3, edges=[FRONT+LEFT], anchor=BOT+RIGHT+BACK);
}