This necklace is built using the 3x3 weave and anodized aluminum rings. The rings contain no nickel, lead or zinc and are hypoallergenic. They will not rust, oxidize or discolor your skin. They are bright, colorful and light weight. If you choose a secondary color option please leave me a note in the special instructions to seller section telling me the secondary color that you would like. The standard length of our necklaces are 18", if you require a different length again just leave me a note and we will make sure it is the correct length.