Nighthawk Custom Adjustable Black Target Rear Serrated Blade/Rounded Corners Fits Bo-Mar 'BMCS' Sight Cut. The square shape of the target sight blade includes rounded edges necessary for carry use without sacrificing sight picture. The rear of the sight features serrations to eliminate glare from light sources while aiming. Some fitting may be required Specifications for Nighthawk Custom 1911 Fully Adjustable Rear Sight: Manufacturer: Nighthawk Custom Color: Black Rear Sight Color: Black Rear Blade Height: 0.325 in Package Contents: Nighthawk Custom 1911 Fully Adjustable Rear Sight Nighthawk Custom SI0049: Adjustable Black Target Rear Serrated Blade/Rounded Corners Fits Bo-Mar 'BMCS' Sight Cut