I used it to cut 6 holes in a batten/stucco ceiling. Although carbide grit is the right tool for the job. This hole saw is TOO BIG for these new LED pucks. I installed the lantern and moved it toward the hole. Around the flange is the newspaper that makes these devices "airy". The holes are large enough that the caulking material does not touch the ceiling. I can put the puck's light on the hole so it closes it - just barley. If you look closely at the attic photo you can see about 1/4 inch around the light fixture. The gasket is useless since I cut those holes. These new LED lights require an upgrade from hole saw manufacturers. I just bought a 4-1/8" hole saw for 4" lights and it's too big too. A 4 inch hole would do! Sorry folks, this isn't the right tool for the job. If you had a 6 inch hole saw this would be perfect. This hole saw will cut holes from 6-3/8 to 6-1/2 when loosened. Do not buy this tool for washer style recessed lights! FAILMy experience as a contractor is over 30 years and I'm still learning every day.