Picatinny rail camera mount.  would not recommend.
919879
The aluminum mounting base is fine but the plastic mounts fit loosely and allow the camera to wobble and the GoPro mounts won't work with it.  Would not recommend this product.
3538114
This little reticle is a disaster, It will not stay on the rail no matter how tight I get it. I was using it on a Sub 2000 Gen 2 and after about a 30 rd mag each time this little sucker would pop right off. I remounted it several times but finally gave up. Might be good for an air rifle.
4912737
I found the mount pretty bad.  The jarring of a mountain bike ride causes it to change position.  Both side-to-side and forward-rear positions were affected.  Side-to-side was really bad.  The fact there isn't a swivel for left/right movement is unfortunate but not a show stopper given the view width of the Hero 4.  I definitely would not recommend this mount.  I've used many bike mounts for lights, computers, video cams (POV & Drift), without issue.
3586842
Not very impressed with this mount, my red dot had an extremely tight fit with the mount which also had many tooling marks and the picatinny base was not level when mounted because of poor machining and/or qc. Sent it back and got the cross machine and tool tactical mount that looks almost the same. And for ~$20 more it is a significantly higher value.
796390
Too small for any decent sized camera, had some play to it with my T3i w/ battery grip and the kit lens. Also, you can't mount it onto a flat surface, there is a part of the locking mechanism that protrudes from the bottom. I would not recommend this.
14829
This rail section is off spec, too tall, and standard Weaver style scope rings will NOT fit. Unfortunately I attempted mounting it to the rifle first before finding this out. The screw heads are slotted and barely deep enough to get a good grip with your screwdriver...AND they are soft and strip way too easily. I am a professional Gunsmith...and this unit went straight to the recycle bin. I do not have time for Chinese crap and wish I'd known of its origin ahead of time. Lesson leaned...cheap is cheap for a reason.
4876973
Had to pound it on the picatinny rail with a rubber mallet and then the quick release would not work. Pounded it off and discarded it.
2761805
I returned the mount. The mount comes in three pieces.  I was not able to snap the pieces together....you need a monster grip.  The only thing that held it togetger was the flexible silicone grip that holds the 4 corners of your phone.  The plastic side mounts are spring loaded to open and close but font actually secure your phone...thats what the silicone piece is for...overly complicated design.  I received an email from the creator with instructions for how to put it together.  I thought that was odd....but the instructions in the box aren't helpful at all..useless is a good word.  The plastic felt brittle/cheap.  The bike clamp was also a problem.  I had to remove the nut completely to get it tight enough on my handlebars and the bolt was about an inch too long for standard handle bars.  It was a very frustrating experience.  I told the creator through email that it was a problem and he seemed to take offense to my honest feedback of his product.  A phone mount should required so much assembly.  They need to keep it simple
4552375
Do not buy this item.  Buy a better quality model.  I mounted this on my Colt 22 and it slides back and forth on the rail.  It also moves side to side.  It cannot be adjusted to a tighter setting.  Also I thought it was all black but mine has "Trinity" painted in white lettering on the side.  It als came with  rust on the bolt and rust in the clear storage bag.  I would not reccomend this riser for anything more than an airsoft rifle or a bb gun you are not too concerned with scope accuracy.  Your scope will move with this riser.  I purchased a riser that is more permanent and got detachable scope rings instead.
1008135
I should have found a more reliable product. On the plus side - I really just needed a riser, the "quick release" was to be a nice plus. No matter how much I fiddle with the tensioning screw and lock nut, I can't find the proper balance between a secure fit and being able to "quick release". (I'm an engineer and I've worked with hardware all my life so I feel fairly comfortable with my comments).

B.T.W. Nice job to VideoPhile for his explanation and review. I can only assume that his success with his mount was due to variance in the manufacturing process and he got a "good one". I did not.

In order for this to work properly for me, I'd need to redesign the cam arm so that there is greater variance between "off" and "tight".

This is another Chinese low quality component. You get what you pay for. :-(

As an aside (and this is true of all risers, not just this one), you will likely need a higher cheek piece on your stock to maintain a good "weld" with this higher mount.
4641763
Got stuck on my camera and had to drill it off...  I wouldn't buy!  Look for something else.  F Grade!
4516619
The Nikon P series mount is well made but it did not fit on my Picatinny rail on my Bushmaster M4A3. Be very leary on this mount.
4036594
Very confused about this product. It's solid, seems well built, and is machined perfectly to fit the Aimpoint Micros. The problem? It will literally not fit ANY picatinny rail that I have tried it on. It will not fit on standard 1913 rails (ar-15), nor will it fit on any bolt on rails (XS scout mount, magpul rails, etc.) The problem is that the quick release lever will not close all of the way once the mount is positioned on the rail. It seems as if there is too much metal in the way on the moving rail clamp.

I am extremely unhappy with the purchase and would like my money back.
3497148
This review was for the roll bar mount I purchased. From the photos it appears to be the exact same design, so this review should apply as well.

This is a flimsy and not well thought out design. Two major problems:

1) Too flimsy. It is made of plastic that bends and stresses when you tighten in down. The cushion rubber pads are lifting after 2 uses because the glue is coming loose. I use it on  boat and it does get exposed to water. But the camera was made for harsh condition so the mounts should be too

2) Both screw closures are not fixed. In other words while attaching or detaching the mount one of the screws comes off (can completely detach) and if you drop it and lose it your mount is useless.

I always use a lanyard if my camera can be damaged or lost by a mount failure.
591382
I would NOT recommend this product to anyone. Not only did it not make it to installation before it broke, it's of an incredibly low materials and build quality. The first thing that happened after I pulled it out of the package to test fit it was that the lever that holds it in position on the wall mounted holder stopped working because the spring popped off the guts of the action. Once I got the spring back on, the post that works as the fulcrum of said lever broke off. This should not be happening on a brand new wall mount. The design of the mount is actually pretty basic and simple and with a few minor adjustments it would be near perfect, but the implementation and choice of weak materials just makes it a total bust.
1060672
The red dot rail mount bolts came stripped. The mount will not tighten. Emailed them and they said they would send a new mount. Still waiting. Other than that the scope is pretty wild. Red blue and green cross hairs. The electronics do not work very well in the cold. (Flickering illuminated lights)
3792111
Broke after less than 50 rounds of 9mm. Would not stay straight as there is no tab on the bottom and only a screw to tighten it with. It is plastic and you cannot get the screw tight enough to keep it mounted straight. Was a waste of time.