The link for the hole saw, when I click it the largest size was 2 and 1/2 not 3". So are you cutting a smaller hole for the 3 " elbow or did they just take the 3" hole saw out of that pkg?
Also I am having a problem with very small wild birds getting into my run and eating the feed will this prevent them from that?
Also I am having a problem with very small wild birds getting into my run and eating the feed will this prevent them from that?