Bag having a handle unit with improved precision of an extendable length

A bag having a handle unit with improved precision of an extendable length, the bag comprising:

• a body;
• and
• a handle unit mounted on one side of the body such that a user carries the body,
• wherein the handle unit comprises:
• a housing coupled with one side of the body and having an installation space therein;
• a foldable section arranged in the installation space and having a configuration in which a plurality of links cross each other such that the plurality of links are extended and contracted in folded or unfolded states;
• a lock gear section that fixes an extendable length of the foldable section and is coupled to an upper end of the foldable section to reduce tolerance occurring when the foldable section is extended and contracted;
• and
• a lock gear adjustment section that adjusts driving of the lock gear section such that the foldable section is extended and contracted according to manipulation of a user.