66lb Max load! Eliptical Ball for progressive resistance. Y-axis diameter 0.03mm longer than the X-axis. Single notch design. Super strong shell. All Metal knobs. For long term durability. Panning Base Scale Independent Pan Lock Knob, 360° panning movement with calibrated precision, precisely capture overlapping panoramic images. Panning Base is laser-engraved with index marks from 0°-360°, with increments at 5° 50mm clamp with Bubble level. Ball Diameter: 44mm. Base: 55mm. Height: 94mm. Weight: 450g. Max load: 30kg (66 lbs). Bottom thread: 3/8" with 1/4" adapter. 1 year Warranty. You can extend the warranty to 6 years with online registration.