Chain length is an important element of a finished necklace. Don't forget - the size of a person's neck and the general size of the person will influence what length you need for a comfortable fit that hangs down to the right place. This model is 5'5" and an average/slim build. A more petite person could have a wider neck and not be able to wear a 16" chain. If there is any question, just have them measure the length they want on themselves with a measuring tape. No tape? No problem. Use a piece of string, mark the length and measure the string with a ruler.