A straight reamer is a cutting tool used in machining to enlarge or finish holes with precision. It features straight cutting edges that help create a smooth, uniform hole diameter. These tools are commonly made from high-speed steel or carbide, making them durable and effective for various materials, including metal and plastic. Straight reamers are often used in conjunction with other tools, such as drills, to achieve the desired hole size and finish. They are essential in industries like manufacturing and construction, where accuracy is crucial for assembling parts and ensuring proper fit.