The small Sea & Sea Sea Arm 8 Strobe Head is a head adapter for an arm set that allows you to attach a strobe or light. It's used to mount a YS series strobe and attaches between a Ball Clamp (#SS-22116) and a Double Arm. The strobe head is constructed of a corrosion-resistant, anodized aluminum alloy and rubber. The unit is 2.73" (6.83 cm) long and weighs 1.49 oz (42.6 g).