Roll cage for the ever popular china 2drJK body, it mounts in the same spots that the factory hard top does when you take it off.
Here's the hardware sizes needed to mount it.
Front(over the windshield):
2.5x6mm(outside where the the factory hardtop mounts) & one 2x6mm button/round head screw & nut in the middle.
Middle(main hoop):
2.5x16mm cap head screw & washer
Rear(down bars):
2.5x12mm cap head screw & washer
Attaching it to the JK body, I find it best to remove the windshield frame from the body & bolt it to the roll bar then reassemble the unit back onto the body & the bolt the rear section on in a diamond pattern(ie: corner to corner) one more thing of note, you'll need to gently squeeze the middle part of the frame over the windshield to get it to line up with the exsiting hole in the top of the windshield frame.
I also offer a version of this roll cage that excepts a light bar.
https://www.shapeways.com/product/P6E6A7HAZ/jk-roll-cage-w-light-bar-mount?optionId=64710694