RailblazaUnisex Railblaza Screen Grabba R Lock, Black

I purchased this item to hold a small iPad on yacht for nav purposes.The central screw which allows bracket to swivel is continually becoming loose allowing the whole thing to wobble about. I have stripped it down several times and even added a spring washer but to no avail. It should have been a decent product apart from this.

Very good product and the best customer service .