FITTEST X4 Low Center of Gravity High Locking Force Panoramic Ball Head with Quick Release Plate for DSLR & Digital Cameras, Load Max 10kg, YT040 X41. This simple structure design, strong durability and high stability, reduce accident rate low center of gravity ball head. 2. Single notch to add contact surface area of ball and shell, increase locking force. 3. Made of aviation aluminum, CNC precisely machined, anodized surface. 4. Main knob designed with ergonomic, excellent touch and grip. 5. Base mount locking knob learn from RRS, adopt star shape anti skid design, increase locking force.