For flaring of copper tube. Creates a perfectly smooth flare. Fits sizes: 3/16-Inch, 1/4-Inch, 5/16-Inch, 3/8-Inch, 1/2-Inch, 5/8-Inch. Will not crush tubing. Fits all standard high pressure fittings. Covered by GreatNeck limited lifetime warranty. GreatNeck has been a hand tool manufacturer since 1919. Our tool brands strive to bring value in design and function. We stand behind our brands and offer an industry-leading lifetime tool promise on workmanship and materials.