ECG23 is D'Addario's lightest gauge of flat wounds. XL Chromes are noted for their smooth feel and warm, mellow tone, essential to the sound and style of many jazz, blues, and rock players. D'Addario XL Chromes are the industry standard in flatwound guitar strings. They deliver a round, full low end without losing punch, making them ideal for jazz players of all types. Wound with flattened stainless steel ribbon wire, XL Chromes are then polished to unparalleled smoothness.