difference(){
translate([0, zbox + ceilth]) mirror([0,1]) {
translate([-SealingBox_lidbigger(),
0])
square([lidoverlap + innertube + tubesealrad,
lidoverhang + innertube + ceilth]);
difference(){
translate([0, zbox + ceilth]) mirror([0,1]) {
translate([-SealingBox_lidbigger(),
0])
square([lidoverlap + innertube + tubesealrad,
lidoverhang + innertube + ceilth]);