What type of nut is used where frequent removal is necessary and the desired rightness is achieved by hand?

Wing nuts are specifically designed for situations where frequent removal and adjustment are required. Their unique shape includes extended "wings" on the sides, which allows for easy hand tightening or loosening without the need for tools. This feature makes them ideal for applications where components need to be frequently accessed or adjusted, providing convenience and efficiency.

The nature of wing nuts makes them especially useful in areas such as assembly or maintenance tasks where speed and ease of access are critical. The hand-tightening aspect is particularly beneficial, as it allows users to work quickly without the added step of retrieving tools, thereby saving time during operations.

In contrast, lock nuts and hex nuts are typically utilized in situations where a secure, permanent connection is important. Lock nuts are designed to prevent loosening due to vibrations, and hex nuts generally require a tool for proper tightening, which does not accommodate the need for frequent adjustments in the same way wing nuts do. Flat nuts do not offer the hand-tightening feature, limiting their functionality where ease of removal is necessary.