I bought this step drill to drill existing holes up to 10mm into the bottom of my Rav4 to install a factory TRD front skid plate. The steel was about 1/8 inch thick. For a hole it worked fine. After that, the drill became very dull and stopped working. I tried to keep the drill bit RPM low and used enough force to avoid premature bit burnout. Still failed. Not recommended for steel or harder materials. Soft materials should work well.