The Manfrotto 176 Set of U-Hooks for Mini Clamp from Lightbulb Rentals is a set of 2 black aluminum U-Hook crossbar holders. They attach to the Super Clamp.
Astera Single Tube Holder$18/day
Cardellini: 3″ End Jaw$5/day
Baby Pin w/ 3/8″-16 Male Thread$3/day
Full-Size Ball Leveling Mount: Aluminum Base (10″ x 14″)$100/day
Sandbag: 35lb$3/day
Square Frame: Straight Coupler (1″)$4/day
Speed Rail: Inner Coupler (1-1/4″)$5/day
Hollaender Fitting: 45° Angled Tee (1-1/4″)$8/day