SMALLRIG15mm LWS Rod Support, Ajustable and Anti-Twist Design, Compatible for SMALLRIG 3196/3680/ 3556/3641/ 3645 Matte Box to Rail Support System, 15mm Dual Rod Clamp - 3652ClimatePartner certified

I use it to mount a matte box on my Z6III. Works great!

SmallRig always makes a nice product. No complaints.

easy to use, and as most small-rig gear bulletproof

If you use this with SmallRig's camera base plate #1674, you'll need a quick release adapter under that to be able to mount your rig on a tripod. (At least I do for my use case using a Benro S6 Pro fluid tripod head.) This support just hangs too low and catches on the tripod. Other than that, it works beautifully to add stability to my rig and provide additional support for my Small Rig mini matte box on my Sony A7III.

I picked this up to help support my matte box and it’s awesome!!!

Well machined. Great fit and finish. I removed the locator pins to use this to stablize my 28-135 lense on a rail system by Tilta. You can use this for more than the small rig map box it was designed for. A bit too pricey though.