Thomastik Infeld Red 4/4 Violin String Set - Medium Gauge with Removable Ball End Gold-plated Steel E Full Set 4/4 Violin Medium Gauge Set Includes Removable Ball End Gold-plated Steel E, Ball End Hydroalium Winding/Synthetic Core A, Ball End Hydroalium Winding/Synthetic Core D and Ball End Silver Winding/Synthetic Core G