A "flexible head" refers to a type of design feature commonly found in tools and equipment, allowing for movement or adjustment in various directions. This flexibility enables users to access hard-to-reach areas or apply force at different angles, enhancing efficiency and effectiveness in tasks. In the context of mechanical tools, a flexible head can be seen in items like ratchets or wrenches, where the head can pivot or rotate. This design is particularly useful in automotive repair or assembly work, where space constraints often make traditional tools less effective.