Thumb Score: +15 Amazon [amazon.com] has the ChromaCast Guitar Maintenance Pack (CC-GM-KIT) for $3.12 + free shipping with Prime [code]╔══════════════╤═══════╗ ║ Lowest │ 3.12 ║ ╠══════════════╪═══════╣ ║ Current │ 3.12 ║ ╟──────────────┼───────╢ ║ Highest │ 19.92 ║ ╟──────────────┼───────╢