Hans Hansen (1884 - 1944) began a major jewelry firm in Denmark. His son, Karl Gustav Hansen, his son, who designed the futurist line of jewelry of which this boomerang necklace and earrings was a part. Currently, the necklace is 5/8" wide and 14 3/4" including an added hook. I can remove the hook and you can use the necklace's own hook, and if you need it, I will send a 3 1/2" sterling extender free. The double boomerang earrings are 1 1/4" by 5/8" with clips. Marked Hans Hansen in script, 925S, Denmark, 318 on all pieces. 1932-1948.