Samson True Back Up Top Mounted Deployable Rear Sight Black. 160 aperture which is small enough for accurate shooting yet large enough to still be of use in low-light environments. Sights lock in both the folded and deployed positions. The durable construction and solid mounting system guarantees you'll stay on-zero. Specifications for Samson True Back Up Top Mounted Deployable Rear Sight: Manufacturer: Samson Color: Black Additional Features: M4 Co-Witness Sight Mounting Orientation: Top Mounted Sight Position: Rear Gun Model: AR-15 Gun Make: AR Platform Front Sight Color: REAR SIGHT ONLY Rear Sight Color: Black Deployable: Yes Fabric/Material: Aluminum Front Material: T-6061 Aluminum Illumination Type: Non-Illuminated Gun Type: Rifle Included Accessories: Standard Illumination Color: None Hand: Ambidextrous Mount Type: Picatinny Features of Samson True Back Up Rear Sight .160 aperture Material: 6061-T6 aluminum Finish: Type III class 2 hard coat anodizing Attaches to any 1913 Picatinny rail Perfect (M4) co-witness height Stainless steel clamp Just over 0.5 MOA per click windage adjustment Precision laser engraving Package Contents: Samson True Back Up Rear Sight What firearm models does the manufacturer say Samson True Back Up Top Mounted Deployable Rear Sight is compatible with? The manufacturer says that Samson True Back Up Top Mounted Deployable Rear Sight is compatible with AR-15Samson 02-00057-01: True Back Up Top Mounted Deployable Rear Sight Black