It's strong but starts to shake once plugged in (24 inches) but the good thing is that it's quiet even though it shakes. It comes with a top post clip to prevent rocking (2 clips, a bottom seat rail clip and a top post clip) but it had nothing to attach the top brace. Now for the easiest part: you have two wide metal brackets (but both were too big) to screw the bottom clamp to the bottom of the rack and then slide the clamp underneath (the screw that holds the seat in place). The problem you are having is that the brace holding the bottom seat clip is too wide not allowing you to slide the seat clip in between the rail and under the seat rail bolt. So you will need a hacksaw to cut the yoke to slide over the guide, and slide to allow the yoke to go under the saddle bolt. I have a car and had to improvise, but I'm sure if you have a full size truck or articulated lorry this will suit you. I gave it 3 stars because I had to make additional modifications (cutting, filing, using a lock washer and blue Loctite) to make it work.
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