I now have 2. One for my Canon 5D Mark IV and the other for my Canon R5. These switches plug in easily and fit firmly. They made this moon shot possible:

The FX9 handgrip cable is well-known for being a little too tight when extended. This add-on takes the stress off

I'm a veteran Hollywood union focus puller and a long time wireless focus user. I've been looking for an affordable, three channel alternative for some time. After using one on a short film in 2015, I decided to purchase this system from Chrosziel. I'm very happy with it so far. Chrosziel is a small company and they are dedicated to customer service. After offering a few suggestions, I saw them implemented almost immediately. The device works as a focus puller would expect. The system is compatible with a wide variety of motors and uses Lemo connectors. It is compatible with Preston motors if you already own those. I have two handsets and send control of the iris to the 2nd handset for the DP. Firmware updates are downloaded from the website and easy to install via a USB stick. If you purchase the option to include the zoom rocker to control the third channel, you won't be disappointed. Together with the software soft stop, performing an on camera zoom while pulling focus is easy. My favorite function of this unit are the 4 programmable user buttons. I expand my stop and focus scale often and with the programmable user buttons, I can set them, cancel them and then recall them.

I have owned one of these since I shot with a 5D mark3. Never a problem. Recently I had to replace , my original because the wire part developed a break in the soft black covering. Great product, in fact, nothing lasts forever.

Performs as expected

After trying numerous follow focus systems including ones that were from the “best” manufacturers, we still had issues getting reliability out of a wireless FIZ control system, and poor customer service even from vendors charging a very high premium for their products. Finally we tried Chroziel and not only did their magnum system work flawlessly, their customer service is great, and best of all if you are using Canon Cine Servo lenses it works natively with them so you don’t need to use as many motors for FIZ control, or depending on the lens you may not need any (i.e Canon 50-1000). This all makes for a reliable, and much more self contained system than any other on the market. I wouldn’t even consider a brand other than Chroziel for FIZ control after using the Magnum.

The MagNum 300 3-Channel Wireless Lens Control System by Chrosziel is intuitive and made for demanding professionals. We have 5 complete systems in our rental inventory, and customers have always been very happy with the performance. Easy to use, clean and streamlined IN-HAND feel, responsive to even the slightest input, and great feedback (feeling) from the actual focus knob. As the owner of over 25 other remote lens systems, the MagNum has been everything we expected!!

This remote switch is great for landscapes, portraits, slow shutter speeds and many other things.

Love this, wouldn't be without it !

The construction is superb! The knurled grip is made of metal and works in all weather conditions and temperatures. Just amazing how Chrosziel continues to do fine work.