This is an adjustable harness that slips over the head, thru the legs, and snap buckls for around girth. I got the small size and it fits perfect for my small dog, a Crestipoo. She walks now with a breeze without choking and the harness doesn't chafe or annoy.

Pros: Adjustable

Cons: none

My dog's prefer their Top Paw harnesses to a traditional collar.

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[updated on 2008-01-18 10:29:06]:
My beagles tend to rough house alot. A regular collar poses a danger in that it can get caught in someone's mouth. The harness allows them to still wear all of their ID tags and not pose a safety risk. These harnesses are easy to adjust and can be thrown in the washer (you may want to take the tags off first!) Inexpensive and can purchase a matching leash.

Pros: Easy fit

Cons: May promote tugging

I was able to adjust this harness just by looking at it before even putting it on the dog. This one is a hot pink. They have great colors.

Pros: Adjusts easily

Cons: no cons

These are nice harnesses. My daughter sells them and uses them on her small dogs. They're non-slip and impossible for pets to get out of.

Pros: ****

Cons: na