You get what you pay for - Magpul Industries MBUS Rear Flip-Up Back Up Sight Gen 2

I regretted this purchase as I pulled it from the box. The sight is massive, far bigger than, say, my Noveske or other, more expensive sights. I have since sold it locally.

Having said that - for the price you are getting a very solid sight that does what it is supposed to do. I like two apertures, don't know how long that spring will hold out under actual conditions, and I won't be finding out.

If you are on a budget, this is probably your best choice, it not, go ahead and spend the money on something better, and more expensive.