scale(10){
difference()
{
    square([43,29.5],true);
    
    translate([20.75,0])
    {
       square([1.5,11.5],true); 
    }
    translate([-20.75,0])
    {
       square([1.5,11.5],true); 
    }
    
    
    
    translate([-20.75,12.25])
    {
       square([1.5,5],true); 
    }
    translate([-20.75,-12.25])
    {
       square([1.5,5],true); 
    }
    
    
    translate([20.75,12.25])
    {
       square([1.5,5],true); 
    }
    translate([20.75,-12.25])
    {
       square([1.5,5],true); 
    }
}}