I worked for a local telecom company for 40 years and have used hundreds of these drill bits during that time. I used them to install CAT Wire 5E on my neighbor's security cameras. The size is big enough for CAT 5E and the length is just right for deeper recesses and thicker walls. You might also want to buy some 12" tips for tighter spaces. These beats feel well made and retain their sharpness. Have a few of these in case one breaks.