Spark Triangular Necklace V Necklace with Swarovski Crystals. With Clear Crystals Specification: Chain is adjustable from 16″ (406.44mm) to 18″ (457.2mm) Gift Box: This item comes with a complimentary gift box. Superior design & quality: Individually designed by Spark in 925 sterling silver using genuine Swarovski Crystals. Hypoallergenic Jewellery: We make all our jewellery hypoallergenic by removing nickel and other metals that may cause allergic reactions. Be assured that our jewellery is safe for you.