Great buis - Magpul Industries MBUS 3 Front Rifle Sight

The MBUS Gen 3 polymer backup sights have very good quality and usability for the price. I have a set of Magpul MBUS Pro metal BUIS on another rifle and, while the MBUS Pro sights seem slightly more durable and have a slightly lower folded height (which can be a plus depending on your scope mount height), the MBUS 3 polymer sights are more than adequate as backup sights as long as you take care not to mount them directly over the gas block (due to heat concerns on their polymer construction), and ensure they will fit beneath your optic when folded (if you need a lower folded height, opt for the MBUS Pros instead). They were easy to zero and so far, after a couple hundred rounds, have held zero. The depolyment button is also crisp and seems durable. Time will tell, but so far I think these are excellent backup sights for their cost and would recommend them to anyone seeking a durable, light, and affordable backup sight option.