The Focus Light Mount with Ball Mount from Beneath the Surface is a combination of 2 mounts meant to enhance your accessory options for your underwater photography tray system. The mount attaches to arm adapters or a bridge bar, depending on your needs and camera set up. It can be adapted to most applications. The ball mount is used to attach an arm system to your tray system. The focus light mount enables the attachment and maneuverability of a focus light. It is designed to fit any 1" (2.5 cm) diameter round body light, including the Underwater Kinetics Super Q light, the Sartek EBL500LIV.