C-Strobe H2O Water Activated Personal Distress Strobe Light. The new water activated C-Strobe from ACR is a feature rich personal distress light that combines intense LED technology with increased operating life to provide you with the ultimate multi-function distress light. The C-Strobe is USCG/SOLAS approved and features an impact resistant case making it a reliable, multi-purpose light whenever efficient distress lighting is needed.