About this 3D model

100mm x 60 mm side is 2mm difference(){ //************************** union(){ cylinder(20,12,12,center); difference(){ translate([-52,0,0]) cube([104,64,8]); translate([-50,2,2]) cube([100,60,8]); }//DIFFBOX }//BLOCK add //******************************* union() { cylinder(21,9.2,9.2,center); translate([-6,-14,0]) cube([12,8,20]); }//remove //******************************** }//diff