If you're a video person but have a photo tripod, this leveling base will give you the ability to level your head much like a traditional video bowl tripod. That means no more fiddling with the tripod legs just to get level.
Quick note just in case it's not obvious: you don't attach a camera directly to this (yea, you could...), It's intended to be used with a fluid head.
-Half the price of similar adapters
-Solid, nearly all metal, no plastic to be seen
-Tightening knob a little loose, works totally fine
-Bubble level is not great, use your head's bubble
-Comes with 3/8 adapter
-Has 3 screws for locking to your head.
-Don't turn the knob all the way to loose, and it'll loosen up better.
The knob is all metal, and its one potential issue is that your tripod may get in the way of it turning, but it has the nice ability to pop out and be adjusted which gets around that. Having to readjust that all the time may be a pain though, so using a spacer, or just getting the knob out of the way of obstruction is more ideal.
The spring within the knob is a bit on the weak side, and feels flimsy, but in practice it doesn't affect the operation at all.
If you're used to true bowl tripods, this doesn't get as loose when you want to adjust it, but for good reason: there's no handle to grip onto for control. I also noticed that if you turn the knob all the way to the loosen position, the base will actually tighten up a bit, so back the knob 1/4 turn from fully loose, and the base will actually get properly loose. Even with that, when loosening i found i needed to give a little wiggle of the head to get it really free.
Ignore it unless you have no other option. The air bubble is small and didn't give me confidence, and doesn't stick out far enough from beneath the head to get a good look at it. Loosen the base and your head's pan lock so you can rotate it into the most ideal position.
There are models from Manfrotto and Sunwayphoto and a few others, but cost around twice as much as this unit. So unless you're already invested in tripods you'd like to use, i would consider looking at some new ones, like the Benro A1883FS2C Aero2 which has a leveling bowl integrated. Or go full video tripod, but of course likely at a higher cost and size.
I do like having this little unit around though, you never know what alternate situations it might end up being useful for!
I'm pleased with the purchase. I've just been dealing with leg adjustments as needed when i can't/won't bring my full size video tripod. This little block of metal just saved me from future leg fiddling.