difference () {
cube([146,103,2],center=true);
translate([-53,16.5,0])cylinder(r=6,h=5,center=true,$fn=80);
translate([-70,-48.5,0])cylinder(r=1.6,h=5,center=true,$fn=80);
translate([70,-48.5,0])cylinder(r=1.6,h=5,center=true,$fn=80);
translate([-25,-41.5,0])cube([30,10,5],center=true);
translate([-70,33.5,0])cylinder(r=1.6,h=5,center=true,$fn=80);
translate([70,33.5,0])cylinder(r=1.6,h=5,center=true,$fn=80);
}