A step drill makes it easy to bore large-diameter holes — or holes of different sizes — in metal or plastic without drilling a starter hole or changing bits. Irwin says its Unibit Cobalt Step Drill is made from M35-grade high-speed steel and therefore cuts faster and stays sharp six times longer than competitive tools. The drill also features laser-etched hole sizes that allegedly won’t wear off. It’s sold in six English and four metric sizes and costs $25 to $70. Irwin Tools, 800/866-5740, irwin.com.
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