It is virtually impossible to hand drill or tap a perpendicular hole without a guide. When properly aligned using a guide, such as the Big Gator Tools line of patented Drill and Tap Guides, drill bits cut faster and taps cut uniform threads. Drill bit and tap failures are also reduced. These guides are manufactured using a heat-treated nickel alloyed steel. The guide base surface is machine-ground to assure stability and perpendicular alignment on flat surfaces. The V-Groove base allows the guide to be positioned on virtually any round object or square corners. Convenient alignment marks on one side of the drill guides center the guide holes over material to be drilled.