The Chicago-Latrobe 255AN series long length drill bit is made from high-speed steel with a black oxide coating and has a 118-degree conventional point for use in deep drilling applications on ferrous materials. High-speed steel (HSS) provides hardness for wear resistance, and the black oxide finish reduces wear while promoting chip and coolant flow. A long length drill bit reaches farther and drills deeper than a jobber length drill bit because it has longer flutes and overall length. The round shank with tang has a flat shank end for use with positive split sleeve drivers and other drills that accept tanged shanks.

Drill bits are cutting tools used to make holes in a range of materials using machines such as handheld portable drills, machining centers, and lathes. Drill bits come in a variety of lengths and types, the most common of which is the twist drill bit. The round, twisted shaft of the twist drill bit typically has two cutting edges and flutes. The helical twist of the flutes brings chips up and away from the cutting edges and allows for coolant to reach the cutting edges. Jobber length twist drill bits, the most common length of twist drill bit, offer a good compromise of length and reach for the widest range of materials and applications. Mechanic's length twist drill bits (also called maintenance length) are a little shorter than jobber length and less prone to deflection when drilling. Short length twist drill bits (also called stub or screw-machine length) are the shortest and stiffest twist drill bits, helping to reduce the chance of deflection or breakage when drilling. Reduced shank twist drill bits (also called Silver and Deming drill bits) have a shank that is smaller in diameter than its shaft, permitting drilling machines with a 1/4", 1/2", or 3/4" drill chuck to create large holes. Long length twist drill bits (also called taper length) are a little longer than jobber length, allowing for deeper holes and longer reach. Extra-long length twist drill bits (also called extension) are longer than long length twist drill bits for greater reach or for drilling deeper holes.
Chicago-Latrobe manufactures drill bits and accessories, reamers, countersinks, and blanks. The company, founded in 1890 and headquartered in Clemson, SC, meets International Organization for Standardization (ISO) standard 9001.