I have a hard time wrapping my head around how one would carve a chain from one piece of wood, let along a chain with no ends, but this carved clearly had some skills, and here one is! I believe this is quite an old one, made of walnut I believe, and it was really beautifully carved, with a slightly squarish shape to the rings, and then one extra at the terminus, just after the ends come together, which makes the perfect loop to hang it from.
12 5/8" long x 2" wide measured as it hangs (the chain itself is about twice that in total length). Excellent vintage or, I would guess most likely antique, condition. Really lovely.