Picatinny rails not standard, if you're planning to mount anything, get something else. - UTG Pro AR15 Extended Carbine Length Drop-in Quad Rail

I would LOVE to recommend this product but simply cannot. Product is solid, easy to install, looks great. BUT, the picatinny rails, NOTHING FITS! Lights, and scopes that fit perfectly on other weapons and their rails will NOT fit on these. My understanding was that picatinny was standard, apparently not. I have taken one light and affixed it to every single picatinny I have, which is numerous, and it will NOT attach to this unit.

The reputation of Leapers UTG is that it is paintballer junk. I had it from some reliable sources that the new line of UTGPRO, all USA made was different. guess not.