The Sea & Sea Sea Arm 8 Double Arm (Medium) is part of a line of modular accessories for underwater housing of DSLR cameras. The SA8 system is intended to connect an external strobe to an underwater housing for a DSLR camera. The SA8 Double Arm (Medium) features ball joints at either end that connect to ball clamps. These ball clamps in turn can connect to Sea & Sea's Slide Ball Base and Strobe Head, to attach an external strobe to a camera housing in a highly adjustable configuration for underwater use. Constructed of corrosion-resistant aluminum alloy with an anodized finish, the arm measures 8.8" (22.3 cm) long and weighs 3.0 oz (83.8 g) on land.