Leofoto XB-38 Pro Ball Head with clam and BPL-50 Plate. Arca compatible with high blocking power this professional ball head is made of high-strength aircraft-aluminum alloy.  Non-slipping, grease-free balls with panoramic floor with dash scale for separate floor rotation. Featuring laser engraved graduated scale provides precise centering and positioning. Smooth friction control with memory function. High precision for offset-free locking.