Meprolt Td Adj For Glk 17 19 20 21

The Meprolight TD Adjustable night sight for Glock 17, 19, 20, and 21 is a self-illuminated replacement sight system engineered for low-light target acquisition. Unlike standard iron sights, Meprolight's self-illuminated night sights use tritium technology to emit visible light under complete darkness, enabling precise aiming when ambient illumination drops below operational thresholds—a critical advantage for law enforcement, military, and defensive carry applications where engagements frequently occur outside daylight hours.

The TD (Target Distance) adjustment feature allows elevation and windage zeroing without tools, a practical advantage during training or duty transitions. The sights install as direct drop-in replacements on Glock Gen 1–4 models; minor modifications to the slide may be required depending on firearm configuration and existing sight cuts. At 0.13 lbs total, the weight penalty is negligible, and the compact profile (4.5 × 1 × 9 inches) maintains slide balance and holster compatibility across standard duty and concealment configurations.

This system is purpose-built for operators, law enforcement officers, and armed citizens who train beyond daylight and require reliable sight visibility in vehicles, low-light buildings, or night operations. Meprolight's reputation within federal and state law enforcement reflects proven durability in field conditions and consistent performance across extended service life. Buyers upgrading from factory Glock sights should verify their slide configuration and existing sight dovetail compatibility before purchase; professional installation is recommended for users unfamiliar with firearm maintenance.