The TPBR bridge was very widely used in the 1960s, on models such as Gibson Gibson SG Special, SG Junior, SG-TV, Melody maker, Epiphone Coronet, Olympic and Kalamazoo KG guitars; it would have been fitted to tens of thousands of guitars.
One advantage of this unit is it can be used just as a bridge, or as a combined bridge/tailpiece; as seen in the first two images below. As a tailpiece, the strings enter the neck-side, then wrap over the bridge; the ball ends of the strings are clearly visible in the second image. Many guitarists prefer this set up, even on guitars with a fitted vibrato, as a guitar with a stop tailpiece tends to stay in tune a little better. There are no saddles, but the whole bridge, can be adjusted to some extenet via the grub screws behind each post. Early examples were nickel plated, later chrome. Identifying this bridge/tailpiece is easy - original Gibson parts have two numbers TPBR8513 and 12809 in the cavities at either end of the bridge. Luckily, this is one of the easier vintage parts to source (see Ebay listings below). more
List of Gibson guitar bridges and tailpieces