Constantly Visible Sight Almost Like Magic!
Unique, universal shotgun sight bead that stays visible in all light conditions: bright sun, heavy overcast, late afternoon shadows, deep woods hunting. Tritium gas light source sealed in the center of a blued steel bead. On bright days, the shooter sees a black bead with a light center. As the light fades, the center becomes a soft green glow. No switches, batteries, wires, or charging. TRU-DOT bead is warranted by factory to provide usable illumination for 12 years.
Big Book Catalog, Issue:70, Page:291
SPECS: .160" (4.06mm) H x .158" (4.01mm) W. .110" (2.8mm) long shank. 6-48 thread.