Complete reel maintenance set Includes 1 Spool Mechanical Knob, 1 gear, and 1 internal sound kit, providing everything you need for smooth operation. Color options light blue, gold, purple, black, red, silver, pink, green, and blue Material and durability Made from sturdy aluminum alloy for longlasting performance and reliable onwater use. Internal sound feature Features an internal sound kit that provides an audible cue during rotation adjustments to aid precise tuning. Function, compatibility, and performance Designed as a replacement for compatible spool knob assemblies, simplifying installation and ensuring you can restore or upgrade reel performance quickly. Durable components engineered to withstand fishing conditions and deliver consistent operation. Use scenarios Maintenance and : worn spool knob and gear to restore smooth operation on an aging reel. Frequent use: aluminum alloy construction supports regular fishing sessions, with the internal sound feature helping monitor and finetune adjustments during use.