Our lawn really got lumpy over the winter. I also decided to over seed the grass and the roller seems to help press out the rough irregular surface at the same time seat the new seed down into the dirt. We got 3/4\"of rain the day after we seeded and we rolled it out and the following night we got 1/2\" and we rolled it out at 90 degree angles. The grass has sprouted and we are waiting for more rain.