Vintage black and white acrylic beaded necklace white spacers and hidden clasp

This is a fabulous vintage beaded necklace featuring black and white acrylic beads, white disk spacers and a hidden barrel style clasp. The highlight of this piece for me is the three mixed black and white beads in front with a zig zag pattern, almost argyle. Unsigned piece. She measures 20 inches long. No extender since the clasp is a hidden barrel. Very good pre-owned condition. There is about 1/4 inch stretch in the string if you hold it up by the end. No stretch visible when wearing.