The Diablo DIB1070 3/8 Inch x 18 Inch Installer Bit is a long-reach installer drill bit built for drilling straight holes in clean wood and stacked lumber during wire installation work. This is an installer bit designed for drilling access holes and pulling wires through walls, ceilings, and floors. Model DIB1070 gives electricians, low-voltage installers, and remodelers a simple way to drill and route cable with one accessory instead of switching tools mid-job.

What matters here is not just the 3/8 inch diameter and 18 inch length, but what those numbers let you do on the job. The slim diameter is useful when you need a clean pass for wire runs without opening up more material than necessary, while the extra length helps you reach through framing members and awkward cavities where a standard bit comes up short. If you are drilling through multiple members in one shot, the long body gives you better access and keeps the drill farther back from tight work areas.

Diablo built this bit around practical installer-focused details. The ultra-sharp tip is meant to start quickly and track straight in clean wood or stacked lumber, which helps when you need the hole to land where you planned it instead of wandering across the face of the stud. The black oxide coated flutes are there for a reason too: they help move chips out fast and reduce buildup, so the bit stays clearing material instead of packing up and slowing down.

Another feature that makes this bit more useful than a basic long drill bit is the small hole in the flute. That hole lets you feed wires and cables through after drilling, which is exactly why installer bits exist in the first place. For electrical rough-in, security wiring, data cable runs, and similar work, that means fewer hand motions and less messing around trying to fish a line through a fresh hole with separate tools.

The 3-flat shank is also worth calling out because it addresses a real annoyance. Long bits can slip in the chuck when the load comes on, especially if you are working through stacked wood or pushing from an awkward angle. Diablo uses a 3-flat shank to help eliminate spinning in drill chucks, giving you a more secure hold in corded or cordless drill drivers.

This is a single-piece installer bit for drill drivers, and it is best matched to clean wood applications, including hardwoods, softwoods, plywood, and stacked lumber. It is not the kind of accessory you buy for general-purpose masonry drilling or metal drilling. You buy it when the job calls for long-reach wood drilling and wire pulling, and you want the bit to do both jobs cleanly.

If you are an electrician, low-voltage tech, HVAC installer, remodeler, or serious DIYer running cable through framed spaces, this bit makes sense. The Diablo DIB1070 3/8 Inch x 18 Inch Installer Bit is especially useful when access is tight, standard bits are too short, and you want a cleaner, faster path from drilling to pulling wire.

Diablo DIB1070 3/8 Inch x 18 Inch Installer Bit for clean wood drilling and wire pulls

This is a purpose-built installer bit that does exactly what you want on rough-in work: drills straight in wood, clears chips well, and gives you a built-in way to pull cable.

• Who it's for: Electricians, low-voltage installers, HVAC techs, remodelers, and DIY users running wire through wood framing.
• Why it stands out: The long 18 inch reach, flute hole for pulling wire, black oxide flutes, and 3-flat shank make it a lot more job-friendly than a basic long wood bit.
• Worth knowing: This is a single installer bit, not a set, and it is intended for clean wood applications rather than all-purpose drilling.

• What kind of tool is this used with? It is designed for use in corded or cordless drill drivers.
• What materials is it meant to drill? Clean wood, stacked lumber, hardwoods, softwoods, and plywood are the intended applications.
• What is the hole in the flute for? It allows users to pull wires and cables through walls, ceilings, and floors after drilling.
• Does the shank help prevent slipping in the chuck? Yes. The 3-flat shank is designed to eliminate or reduce spinning in drill chucks.