SMALLRIG Rotatable Collar Horizontal-to-Vertical Mount Plate for Sony A7R V / A7 IV / A7S III / A7R IV, Rotating Collar for Arca-type and for Manfrotto RC2 Plate - 4148. Compatibility - SmallRig Rotatable Baseplate 4148 is designed for Sony Alpha 7R V / Alpha 7 IV / Alpha 7S III / Alpha 7R IV.
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