75mm Black Magic® Airblocks feature Torlon® roller bearings and carbon-black balls for strength and reduced wear. The unique center cage separates rollers for less friction and sideload ball bearings are protected by sculpted aluminum sideplates. Dissimilar metals are isolated to minimize corrosion. The three-way head swivels/locks in front/side positions. Blocks are easily disassembled with a single Allen wrench.