K3 super bright color designed to sound clear, bright and musical. In order to create a very unique Bajo Quinto set, we have used four different materials which are Stainless Steel and Nickel Plated Steel with K3 Color plus a combination core wire. .060 & .080 - Stainless Steel bass strings are round wound and constructed upon a round core with loop ends. Both of these strings will provide highly flexible and musically bright and warm strings. .026, .036, .046, .030 - strings are Nickel Plated Steel on a Hex core with loop ends. All 4 strings will compliment with the Nickel bass strings with highly warm and bright sound. DR NEON is applied to provide a long lasting string with a super bright glow. Bright in the day light, or under stage lighting. DR NEON Bajo Quinto strings "pop" in appearance, sparkle brightly, and are black light active plus glow amazing under UV lighting.