Free Express Shipping! Acratech Video Adapter w/ Arca-Style Clamp For Using a DSLR w/ Arca-Style QR Plate, Attaches to Fluid Video Head, For DSLR Video Production, CNC-Machined, Stainless Steel Hardware, 1/4"-20 and 3/8"-16 Threads, 0.6" Leveling Bubble