Kaplan Solutions Violin String, E , Ball - medium - 4/4 from D'Addario.
The Non-Whistling E String produces a sweet, warm, and rich tone that blends well with the lower strings of the violin.
It is specifically designed to eliminate the whistling sound sometimes heard when the open E string is played while crossing from a lower string.
A free ball-end adapter is included with the Kaplan Solutions Non-Whistling E for installation on instruments equipped with a single hook-type (loop-end) E-string fine tuner.