Thumbs, nuts and washers are small but essential parts for the assembly and adjustment of percussion instruments. Each one fulfills a specific function:

1. Butterflies: Used to adjust parts that need to be clamped or tensioned, such as drum heads. Its design allows for quick and easy adjustment without the need for additional tools.

2. Nuts: These are essential for securing and securing instrument parts, such as drum components, cymbals, or other adjustable items. They ensure that the parts remain in place while playing.

3. Bushings: They are placed inside the acorn to adjust the screw when tuning and distribute the pressure evenly.

In short, these parts help maintain the stability and sound quality of percussion instruments, allowing for precise adjustments and ensuring the durability of the instrument.