Connection that works to temporarily or permanently close a conduction line in a pipeline.  It is designed in copper which allows it to be an excellent material to comply with the strict standards of the industry, making this product more effective, efficient and resistant in its use. These nuts are characterized by having a deformation in the thread that does not allow them to move or loosen with vibrations or movements, making them very useful. Their resistance to vibrations makes them the best option.  This nut for refrigeration is 3/4".