This is just an "E" string from Eurosonic. It is light gauge, chromesteel on steel rope.
Eurosonic Orchestra strings are impressive for their clear (not scratchy) sound and long life.
Construction is a steel-rope core, with chromesteel winding. The light gauge is the most versatile, more like a regular or medium gauge in other brands, while the "medium" gauge is heavier and stiffer than medium in most other brands. Both tend to make basses sound loud and clear without being overly bright. Overtones and harmonics are clear, and string crossings are clean and easy to achieve, without being scratchy with the bow.
Not sure which strings to purchase? Check out our comprehensive guide!