Sealey-AK8187-Step-Drill-Screw-Bolt-Extractor-Set-10pc-Sealey-AK8187-Heat-treated-Chrome-Molybdenum-steel-screw-extractors-&-fully-ground-step-drill-bits-Ideal-for-removing-right-h&-thread-broken-seized-screws-&-bolts-Step-drills-produce-a-conical-hole-which-when-used-with-the-corresponding-extractor-provide-increased-grip-to-easily-remove-damaged-fitting-Special-design-of-the-extractors-cut-into-the-side-of-the-hole-allowing-increased-force-&-make-removing-heavily-seized-fittings