D'Addario Prelude Violin Single D String, 4/4 Scale, Medium Tension 4/4 scale violin with a playing length of 13 inches (328mm) Medium tension Solid steel core optimized to create the warmest-sounding student strings available Educator's preferred choice for student strings due to their unique blend of warm tone, economy, and durability All D'Addario strings are designed, engineered and manufactured in the USA to the most stringent quality controls in the industry