Heat resistant speedrings for the most popular flash brands. Our line of speedring adaptors makes the HR softboxes compatible with 9 different flash brands, including the most popular manufacturers of professional studio light equipment. So, even if you own flashes from many different manufacturers, you only need one brand of softboxes! Use one brand of softboxes for many different manufacturers. The speedrings are designed so that the HR softboxes can be rotated 360°. Designed to withstand years of professional use.