This is the replacement flash tube for the Flashpoint Ring Li-on, the 400ws lithium powered, self-contained ringflash system optimized to meet the vision of the ever innovative creative professional photographer. This rugged 400ws flash can light beautifully - whether for macro detail, fashion excitement, portrait (for key, fill or catch light) effects or for traditional softbox/umbrella applications with the freedom of reliable lithium energy. An excellent light source for stop action fashion sequences or applications and specialty lighting requiring edge to edge illumination, this is a spectacular performer with a solid guide number of 82 (ft. @ ISO 100), rare power for portable ringflashes