Feature:

1.Doulbe End,double performance life.

2.Usually recommend for all sheet metal drilling applications.

Others related:

Double End drill ,as one of kinds of twist drills,it has the same function as other twist drills,twist drill is for drilling round holes of workpieces by rotating Cutting relative to a fixed axis.  It is named for its spiral-shaped chip holding groove, which resembles a twist.  Spiral grooves have 2, 3, or more flutes, but mostly is 2 flutes.  Twist drills can be clamped on hand or electric hand-held drilling tools or drill presses, milling machines, lathes and machining centers.  The drill material is usually high-speed tool steel or carbide. Twist drills are generally divided to: straight shank, reduced shank and taper shank, the difference between them is that the straight shank and reduced shank been used with drill chuck; while the taper shank twist drill shank is tapered shank end has a flat tongue, which can be directly clamped to machine tool to process parts, or mounted to the drill bushings and then clamped to machine tool to process parts. Straight shanks are used for small drills and taper shanks are used for large drills.