LaserMax Guide Rod Laser for Glock Generation 4 Model 20/21/41 N/A Made in US Red Guide rod laser for Glock Gen 4 model 20/21/41 Distinct ambidextrous activation switch Internal design will not interfere with holster or grip selection Guaranteed Factory Alignment Installs in minute; Class IIIa Laser Product: &lt;5mW power output Class IIIA laser, &lt;5mW power output