We all know that a dog's collar should fit snuggly, but with enough room to allow two fingers to slip underneath it. But where on the dog's neck do you measure that? Trink's got a roughly triangular neck. If the collar is tight up by the ears, she will choke if it slides down her neck. And if it fits down by the shoulders, it's almost falling off up by the ears. So... do you pick the middle of the neck, or what?

I have 2 collars on my Jack Daniels (Russell). One is a slip chain that I use to clip her leash to and the other is a blue web style that I have her license tag on. This blue collar is loose on her neck. I use the slip chain collar to keep her from slipping the blue collar and chasing cars or cats. The dual collar thing works for my Twinkie. I take off the chain collar when in the house and just leave the blue collar on. For an 11 lb dog she is quite strong.

A trainer will often say to keep it high on the neck, easier to make corrections when on a leash. I've got one of those freakish dogs that's head is smaller around than her neck. She is able to escape in ANY flat collar OR harness in her fearful fits, so we now use a nylon slip collar.

I should clarify... when on walks I am currently using a harness due to some neck issues. The collar I am concerned about is the one with her tags that she wears 24/7.

Just make sure that she cannot slip her neck out of it herself. If you keep the collar at a comfortable loose setting (like what is pictured in your picture) your dog will be okay. You've already solved the walking problem by using a harness.