Maestro Vibrola, manufacturer unknown. I acquired this 7-8 years ago and had it mounted on an SG-type guitar, but I'm selling it because I no longer need it after getting rid of the guitar. It may be difficult to see in the pictures, but the tarnish characteristic of nickel plating gives it a vintage feel. The screws in image 4 are not the original ones, but there are no issues with installation. Please note that it may not be possible to install this on all guitar types. Thank you.