Very thick steel. I had to deburr the metal a bit, no big deal. It's good quality and price. My thoughts. The thickness and heaviness of the saw was an issue for me, my drill bit is quite powerful; which was also a factor. The mass of the saw during operation was staggering and dangerous to say the least, an inherent hazard of using a saw with such a large surface area. Butt. Be aware of your surroundings because if you don't get it right it will jam and rebound. On my sixth hole, I lost my footing and the saw kicked off the chuck and caused damage. Luckily for me there wasn't a body around. My story, learn from it. It was user error, but don't think it can't happen to you. Switch on personal protection. eyes and nose and mouth.