The Hydrostat is our most advanced ball head, designed to meet the demands of professional photographers for a lightweight, but at the same time heavy duty load capacity head. This model has similar features to our standard range of ball and socket heads, with independent pan and tilt locks, 360° pan and +90° / -90° tilt movement - but employs a revolutionary friction and locking mechanism. An inner oil chamber is compressed by turning the locking knob, exerting even pressure on the whole of the underside of the ball, which ensures sturdier locking and higher capacity..