I second the two fish lock blocks . Solid reliable design. Never had a light fall out or any part of the clamp slip or move at all on the bars even when wet. Quick removal. Commuted to work with them for a year and continue to use them. The rechargeable AW liion cells I've been using in my now vintage incandescent surefire flashlights since 2008 are beginning to not hold a charge. The lights worked OK .. I upgraded one with a brighter LED lumensfactory drop in lamp module but I'm looking into a purpose made bike light for my next setup.