Light Widow FIZLock: The Universal FIZ Motor Mount That Speeds Up Lens Changes

Last updated: 7 August 2026. Prices are in AUD and correct at the time of writing, check the linked product page for live pricing and stock.

The Light Widow FIZLock is an articulating FIZ motor mounting arm, a “dogbone”, that lets a focus puller fine-tune how a lens motor engages the lens gear, then disengage and re-engage it in seconds for faster lens changes. It's a small bracket that solves two everyday problems on a cine set: getting the motor perfectly meshed, and not losing that position every time you swap a lens.

What the FIZLock does

FIZ motors (focus, iris, zoom) drive the lens through a gear that has to mesh precisely with the lens gear. Too loose and the gear skips under load; too tight and it binds. The FIZLock's articulating arm lets you position the motor exactly, engage it with the right mesh, and lock it, so your focus pulls stay accurate.

Faster lens changes

The clever part is the quick disengage. Instead of loosening the whole bracket to change a lens, you back the motor off by just a few millimetres, swap the lens, and re-engage, without losing the motor's previous position. On a busy set that's seconds saved every single lens change, and it keeps the AC's carefully dialled-in engagement intact.

Pre-load for high-torque motors

The FIZLock also lets you engage the motor with a little added pre-load, slightly over-engaging the gears, which matters with high-torque motors on flexible 15mm rod setups. That extra pre-load means there's no chance of the gears disengaging mid-take, even when the motor is working hard.

Universal motor compatibility

It's built to be motor-agnostic. The FIZLock is compatible with any motor system that uses 15mm or 19mm rod mounting, including cForce, Preston, Teradek, Tilta and DJI, so it fits the controllers most AC carts already run.

Who it's for

First ACs and focus pullers who run wireless lens control and change lenses often, narrative, commercial and documentary crews alike, get the most from it. If you've ever lost a good motor position to a rushed lens swap, this is the fix.

Frequently asked questions

What is the Light Widow FIZLock?

It's an articulating FIZ lens-motor mounting arm (a dogbone) that lets you fine-tune how a lens motor engages the lens gear, then quickly disengage and re-engage the motor for faster lens changes without losing its position.

What motors is the FIZLock compatible with?

It works with any motor system that uses 15mm or 19mm rod mounting, including cForce, Preston, Teradek, Tilta and DJI.

How does the FIZLock speed up lens changes?

You disengage the motor by just a few millimetres to swap a lens, then re-engage it, without repositioning the motor, so you keep the exact gear mesh you set and save time on every change.

What is motor pre-load and why does it matter?

Pre-load means slightly over-engaging the motor gear with the lens gear. On flexible 15mm rod setups with high-torque motors, that extra pre-load keeps the gears from disengaging during a take.

Where to buy in Australia

Black Flag Distribution is the official Australian distributor of the professional film, television and production brands featured in this guide. We supply an Australia-wide network of authorised retailers and stockists rather than selling direct to the public, so there is a local dealer who can help wherever you are. To check pricing and availability and to buy, use the Black Flag Distribution store finder to find an authorised retailer or stockist near you. Search our store finder to locate your nearest Australian stockist and purchase from an authorised dealer.