It's no too late for grass seeding but I am planning ahead for September.

I have read about "slit seeders", which are upposed to dig lightly into the
soil and insert seed into the slits. Our local rental place says there is
no such thing; what they want to rent to me is a power rake with a seed
hopper behind it, so you are raking the soil and then dropping seed
immediately behind the rake (but not particularly targeting the seed at any
cuts in the soil). I can do that myself by raking and then scattering seed
separately later; this process does not seem to help much in getting the
seed to make good contact with the soil.

Is the rental machine I described the same thing as a slit seeder, or do I
need to look harder for a real slit seeder?