Magpul Industries MBUS 3 Back-Up Rear Sight, Rapid-Select Rear Aperture System, Ambidextrous Push-Button Deployment, Fits Picatinny Rails, Black MAG1167-BLK
Specifications:

Type
Frame Material	Polymer
Frame Color	Black
Firearm Fit	AR-10/AR-15/M-4/M16/M110/SR-25
Base Configuration	Picatinny Rail
Style	Folding Back Up Sight
Front Material
Rear Material	Polymer
Front Color
Rear Color	Black
Rail Size
Windage Adjustment	0.5 MOA/ 0.4 MOA
Elevation Adjustment
Fiber Diameter
Firearm Type	AR Platform