Very solid, and well crafted. They are very tight fitting and have ridges so they don’t require any kind of adhesive to stay in place. You need to give them a good press to get them in. The nickel looks great.I used them on my Squier Jaguar bass to convert it to a string through. They are large even for bass ferrules. I included a picture of the front because I used ferrules in front too. They are a different brand that had a smaller external footprint. I included it so you can see a comparison in size.I used a drill press and a forstner bit to make all the holes. I practiced on scraps until I had the depth right.