Add a simplecase

wand = [2, 2, 2];

sds011 = [71, 71, 28];

sds011_anluft = [10, wand.y, 10];

sds011_anluft_offset = [wand.x + 15, 0, wand.z + 10];

esp8266 = [38, 71, 13];

esp8266_usb = [wand.x, 20, 13];

esp8266_usb_offset = [0, wand.y + 5, wand.z];

difference() {

    cube(sds011 + wand + [wand.x, 0, wand.z]);

    translate(wand) cube(sds011);

    translate(sds011_anluft_offset) cube(sds011_anluft);

}

translate([0, 0, wand.z + sds011.z]) difference() {

    cube(esp8266 + wand + [wand.x, 0, wand.z]);

    translate(wand) cube(esp8266);

    translate(esp8266_usb_offset) cube(esp8266_usb);

}

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