This self-locking wire and cable management grommet is great for use in walls, ceilings, floors, computer workstation desk tops, entertainment centers and endless other applications. Installation: A unique and better grommet to do the job right. Once surface opening made, no tools used. Grommet wings are retracted and then activated for insertion into surface and securing/locking into position by simply turning the pass through tube. Once wires/cables in position, place finishing cap on tube. Grommet is reusable for future relocations. Length: 1 3/4″, Width of outer surface rim: 2 3/4″, Wire/Cable pass through inner diameter: 1 1/2″, Mounting surface thickness: 3/8″ – 1″, Hole saw bit size: 2 3/8″ or use any sheetrock type hand saw- Patented