Fotodiox 10SPRPPT Speedring for Profoto Compact Lights Series D1 250 , D1 500 , D1 Air 1000 , D1 Air 500 , Pro Series Acute B 600 , Pro-B 12000 , Acute 2-D4 Strobe Flash Light and Speed Ring
The Fotodiox dedicated speedring is specifically designed for your strobe light to fit standard softboxes both rectangular and octagon boxes. It has a outer diameter of 7 5/8" (19mm), fits 1/4" (6mm-7mm) standard rods. It fits all Profoto Strobe.