Luth-AR Retro A1 Rear Sight Assy w/Retro Windage Knob Black. It features a sleek durable design and Retro Style Rear Sight Windage Drum making it easy to get the perfect shot every time. Whether youre hitting the range or hitting the field this sight will help you shoot with confidence. Specifications for Luth-AR Retro A1 Rear Sight Assy w/Retro Windage Knob: Manufacturer: Luth-AR Color: Black Package Contents: Luth-AR Retro A1 Rear Sight Assy w/Retro Windage Knob UR-09-E3-R: Retro Style Rear Sight Windage Drum UR-11-E3: Rear Sight Detent UR-12-E3: Rear Sight Detent Spring UR-13-E3: Rear Sight Aperture UR-14-E3: Rear Sight Windage Screw UR-16: Rear Sight Base Roll Pin UR-28: Rear Sight Flat Spring Luth-AR UR-21A-R: Retro A1 Rear Sight Assy w/Retro Windage Knob Black