A reference bits primary application is to be used as a reference point to measure from when having to drill in a specific wall cavity (i.e. drilling down through top plate in wall with stapled bat insulation, up from basement in wall with blown-in cellulose or Styrofoam insulation). The hole created is so small that it will remain unnoticeable, even on a ceiling.
Don't Drill Blind! Use a Reference Bit First!
These small diameter reference bits allow you to drill a reference hole through material to check for obstructions, knots or other undesirables, and as a reference point to measure when drilling up through a top plate, or up from the basement through any kind of insulation. The hole created is so small it will remain unnoticed and does not need refinishing. Simply cut at an angle to create a point the length you will need, and drill. When using, the drill chuck must be fully closed and tight.
The Reference Point Bit is an extremely small (0.047" diameter) wire bit for preliminary identification of drill bit path. Made of 36" long spring wire, this bit can be cut at an angle and any length to make the smallest reference bit. Packaged as a convenient 10-pack.