Steel Grade: SAE1060, SAE1065, SAE1070, 60#, 65#, 65Mn, 70#, 72A, 72B, ... ~12.00mm 1. Product Name: High Carbon Steel Wire, Spring Steel Wire, High Carbon Spring Steel Wire, Carbon Steel Wire, Spring Wire, Mattress Spring Wire, Spring Wire for Mattress2. Material: MaterialCarbon ... , Bangladesh, Sri Lanka, Iran, Israel, Brazil, South Africa Hard Drawn High Carbon Spring Steel Wire for Mattress