Gitzo Center Ball Head Series 1 Quick Release D Gitzo’s Center Ball Heads are extremely balanced & versatile heads, engineered & designed focusing on ultimate smoothness & precision of the movement & locking. GH1382QD is the medium sized head, designed for Series 0 & 1 Mountaineer tripods, & also fits between the folded legs of Series 2 Traveler tripods. Despite its slim design, it is fully featured including the friction control knob positioned inside the ball locking knob. It is supplied with the short, Arca-Swiss compatible plate (GS5370SD), but is also compatible with all of Gitzo's D profile plates & fits most Arca-Swiss style plates from other brands.