1Excellent Materials: This diamond core drill bit is composed of premium alloy steel components and excellent diamond abrasive grains, with 10.6in drill length, ensures longer core life. 2Standard Thread: Featuring 5/811 universal thread, this core bit can be easily and quickly assembled to a standard fixed or hand held drill machine, which is applicable to various devices. 3High Performance: The drill bit is designed with chip removal holes, highly regular saw teeth and concentric shaft, enables high drilling performance while maintaining a long service life. 4Wet and Dry Drilling: Core drill is available for both dry and wet drilling to suit your job needs, a small amount of water can extend the lifespan. 5Wide Usage: Can be used to drill concrete, red brick, marble and other materials when air conditioner installation, plumbing installation, stair railing installation, highway and airport, etc.