SLIK SBH-320 Professional Ballhead 320 with DQ-L Quick Release, Supports 15.4 lbs., Black (618-320) Part of the Professional SBH-series ballheads, which are made with exceptionally fine machining and carefully anodizing of hardened aluminum parts that are designed to give many years of trouble-free super smooth operation All-metal construction Panning base, with degree markings Base diameter of 2.3" (58mm) DQ-L quick release system