UAG 600nm shock rated red laser to 500yds (never use it that far). Windage and elev. adjusted to barrel parallel, gives known 1 1/2" holdover. 1/2" dot at 100yds. Lots of fun with illuminated mil-dot.
Works with scope for training young or inexperienced shooters in eye relief, cheek weld and distance estimation w/mil-dot chart and 1' ruler at target. Surprisingly visible in daytime.