11pcs Spiral Type Deep Extractor Set 6mm - 19mm Genuine Neilson - CT6064. The manufacturer part number is CT6064, and the set is sold as a single item. And the spiral deep extractor work on sizes - 1/4"" (6mm), 5/16"" (8mm), 3/8"", 7/16"" (11mm), 1/2"", 9/16"" (14mm), 5/8"" (16 mm), 11/16"", 3/4"" (19mm).