SN1770OS-Z Zoom Gear ~for Sigma 17-70mm F2.8-4DC Macro OS HSM canon The Flash Trigger allows for

The Flash Trigger allows for rapid fire manual flash firing via fiber optic

An optional LCD window (p/n #17171)

This kit replaces the standard handle top-mounting plates to allow for the mounting of the Nauticam Atomos Shogun Housing on the NA-A7S/A7II/A9 housings

This mechanism can also be removed

Instruction Manual PDF Download

SN1770OS-Z Zoom Gear ~for Sigma 17-70mm F2.8-4DC Macro OS HSM canon The Flash Trigger allows forZoom gears allow access to the mechanical zoom function of supported lenses. Use of this gear may require the use of additional port extensions or adapters. Check the Port Chart for more details. This zoom gear is for the Sigma 17 70mm F2. 8 4DC Macro OS HSM (Nikon mount) lens. Product Manual PDF