Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights 2 Dot Rear / Orange Hyper Bright Front Black. FRBS sights are advanced low-profile durable tritium-enhanced auxiliary front and rear back-up sights. The sights quickly fold up or down depending on the shooters needs. Sight pin elevation is easily and quickly adjusted without tools. FRBS sights are readily mounted on any 1913 Picatinny rail. Day or night the tritium makes the FRBS a viable option. Specifications for Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights: Manufacturer: Meprolight Condition: New Gun Model: Universal Front Sight Color: Orange Fabric/Material: Polymer Fiberglass Illumination Type: Tritium Gun Type: Rifle Mount Type: Picatinny Attachment Type: Picatinny Features of Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights Low profile and lightweight design Can be used as a primary or back-up sight Manually adjustable no tools needed Durable fiberglass reinforced polymer and metal construction Spring-based locking mechanism will not break or deform Compatible with all MIL-STD 1913 Picatinny rails 12 years warranty for Night Sight luminance Package Contents: Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights What firearm models does the manufacturer say Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights is compatible with? The manufacturer suggests that Meprolight MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights is compatible with UniversalMeprolight 403220: MEPRO FRBS - Self-Illuminated Flip Back-Up Rifle Sights 2 Dot Rear / Orange Hyper Bright Front Black