The package said that it had instructions with it but I couldn't find them.  Not a big deal because I have a straight shaft weed trimmer and it was very easy to install.  One nut is all it takes.  As for a curved shaft there is more hardware and seems more involved.

I replaced the line that was in it with red .105 pulverizer line.  I made it as long as I could without hitting the side of the trimmer.  I trim the whole yard without having to change lines but as with any, and I've even do it with this, if you trim a lot of fence or sidewalk or driveway you can eat it up jus like any other.

With four lines as long as they can go the sound it made when I ripped it brought out the Tim Taylor in me. It sounded like it could really tear stuff up.  The orginal head has two lines and this four, I noticed that with all those lines it labored the motor.  As the lines get smaller of course it's not as noticeable.  It's not really an issue but I make the lines a littlle shorter just to make it easier on the motor.  The line is easy to switch out if you need it, no trouble there.  I hope that the the plastic holds up and the little pieces that you push the line through.

I only take a star away because there needs to be a raised bumper between the ground and head.  You will scalp the ground for a while untill you get used to it but with the original head (at least on my trimmer) it had a plastic bumper.  This head needs something like that that will help prevent you from scalping the ground.  As I said you will get used and learn how to angle it so you won't have bald spots all over the place.  Overall I would recommend this.  They have a head that will hold like .130 line and I wish I would have bought but this will do!
The package said that it had instructions with it but I couldn't find them. Not a big deal because I have a straight shaft weed trimmer and it was very easy to install. One nut is all it takes. As for a curved shaft there is more hardware and seems more involved. I replaced the line that was in it with red. 105 pulverizer line. I made it as long as I could without hitting the side of the trimmer. I trim the whole yard without having to change lines but as with any, and I've even do it with this, if you trim a lot of fence or sidewalk or driveway you can eat it up jus like any other. With four lines as long as they can go the sound it made when I ripped it brought out the Tim Taylor in me. It sounded like it could really tear stuff up. The orginal head has two lines and this four, I noticed that with all those lines it labored the motor. As the lines get smaller of course it's not as noticeable. It's not really an issue but I make the lines a littlle shorter just to make it easier on the motor. The line is easy to switch out if you need it, no trouble there. I hope that the the plastic holds up and the little pieces that you push the line through. I only take a star away because there needs to be a raised bumper between the ground and head. You will scalp the ground for a while untill you get used to it but with the original head (at least on my trimmer) it had a plastic bumper. This head needs something like that that will help prevent you from scalping the ground. As I said you will get used and learn how to angle it so you won't have bald spots all over the place. Overall I would recommend this. They have a head that will hold like. 130 line and I wish I would have bought but this will do!