The U-55 Double Accessory Tray from Cambo mounts under the U-4 or UBA crossarm. The trays enable you to access accessories you might need while shooting such as lenses, light meters, film or memory cards. Both trays swivel, allowing you to move them to where they are convenient.
In the Box
Cambo U-55 Double Accessory Tray for U-4 and UBA Crossarms