Manufactured By is usually credited on the text at the edge of the label.
Records pressed by the Federal plant can be recognised by the etched matrix prefix FRM or F.R.M. and releases often show the letters F+R, joined by a cross or dagger, in the run-out area.
The same prefix may also still appear on releases pressed from the original Federal plates and at times a plate made elsewhere may have been used for the other side; for these editions, unless otherwise specified, a 'Mastered At' credit is more appropriate.
On some pressings the matrix prefix may be only an F, followed by the producer's initials [e.g: FPB = Mastered @ Federal and Produced by Prince Buster].