Soft Flex beading wire is constructed of micro woven stainless steel wires:

Soft Flex Beading Wire is strong and flexible. It can be used with Czech Glass Beads, Swarovski Crystal Beads, Metal Beads and Gemstone Beads. All stainless steel used in Soft Flex wire is 100% recyclable. The spools and clips can also be recycled - just tear off the label and put the empty spool into your recycling bin. 

Soft Flex Black Onyx Fine Beading Wire Specifications:

• Color: Black Onyx
• Category: Beading Wire
• Strength Test: 10 lbs - Fine
• Number of Strands: 21
• Material: Stainless Steel 
• Diameter: 0.014 inch
• Quantity: This Soft Flex Black Onyx Fine Beading Wire is sold on a 10 ft spool