I bought this for my boyfriend and he fell in love with it.  He put them on right away (I bought the necklace and bracelet) and he said that his old sports-injured shoulder felt better immediately (likely a mind-over-matter situation, but hey...I'm not complaining and neither was he)!  He wears the necklace everyday...  He has a 17.5" neck and the 18" necklace fits good...short on his neck/chest but not too tight.  He's a muscular guy so it looks killer on him.