From Elixir:

The longest lasting tone night after night!

Elixir^® Electric Nickel Plated Steel Strings with OPTIWEB^® Coating give you the performance of a natural string — that crisp tone, natural feel and playable grip you know and love—without sacrificing the signature long-lasting tone life of Elixir Strings.

• Played for the same crisp tone as an uncoated string
• OPTIWEB Coating provides a natural feel
• Electric guitar strings constructed with nickel-plated steel wrap wire
• Our coating technology protects against common corrosion and debris buildup, extending tone life longer than any other brand’s coated or uncoated strings*
• Anti-Rust Plating on plain steel strings ensures longer tone life for the entire set
• With less hassle and expense of frequent string changes, spend more time making music