This adapter ring has been perfect for me to use a Nikon 50mm f1.8G lens on my Lumix GH4... for the price it is great, it is not too heavy and works excellently and smoothly. The only thing is that the aperture ring may not give you all the aperture steps, if there are 15 for example it goes from the first to the last but it may miss some in between, or at least that is my feeling, apart from the fact that it is not marked what number of aperture you would be using, but let's be realistic it is a manual adapter, let's not ask for pears from the elm tree and at that price.
It comes in its box well protected by bubble wrap and as an observation it does not have any type of caps, something to keep in mind if you want to carry it loose.

As a detail to highlight, at first the adapter did not fit well with the lens because I put it in its position but it did not finish turning until the butterfly screw made a "click" at the end of the travel and I did not force it, the cause was that although they are polished metals they do not come with lubrication for obvious reasons, so when you get to that "stop" you just have to apply a little more force turning (don't worry, nothing will happen) and at the same time apply a little pressure up and down intermittently until it clicks... it is only the first time, the others are already more fluid... I hope it helps :)