TRUGLO TFX Pro, Sight Set, Fits FN FNX 40, Tritium/Fiber-Optic, Day/Night Sight, 24/7 Brightness, Orange Ring on Front Sight TG-TG13FN2PC Glowing bright both day and night" TFX Pro sights are always ready. TFX Pro takes their award-winning Tritium + Fiber-Optic technology even further with all the features their customers requested: compact snag-free design" longer sight radius" and amazingly durable construction built to handle just about anything. Illuminating elements are encased inside a virtually indestructible chemical and shock-resistant capsule and the CNC-machined steel is protected with a rust-resistant FORTRESS FINISH. Please note that items TG13BR1PC and TG13SJ1PC are front sights only.