7 Piece Metric Set TSMS5107B [14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 21mm ] TurboSocket is the original damaged fastener removal tool. American-made for over twenty years, our unique tapered helical flute design is the key, in addition to our high-quality machining, heat treat, and plating processes. TurboSockets are unequaled in removing rounded off bolts, nuts and screws with tapered or rounded heads. Also effective in removing or loosening corroded fasteners, oil pan plugs, manifold nuts and even slotted or Phillips head screws that are too tight to be removed with a screwdriver.