translate([0, (sonar_holder_width + sonar_holder_depth) / 2, 0]){
cube([sonar_holder_depth / 2,
(sonar_holder_width - sonar_holder_depth) / 2 + 0.8,
sonar_holder_depth]);}
translate([-1.7, sonar_holder_width + 0.8, 0]){
linear_extrude(height = sonar_holder_depth){
translate([0, (sonar_holder_width + sonar_holder_depth) / 2, 0]){
cube([sonar_holder_depth / 2,
(sonar_holder_width - sonar_holder_depth) / 2 + 0.8,
sonar_holder_depth]);}
translate([-1.7, sonar_holder_width + 0.8, 0]){
linear_extrude(height = sonar_holder_depth){