The 1590B enclosure: It's die-cast aluminum. It's shrink-wrapped. It comes with 4 screws.
And, in my opinion, the aluminum machining looks way nicer and more finished than what I used to get from the big suppliers (before I started sourcing my own).
The 1590B enclosure is similar to the Hammond 1590B and 1290. Remember that there are LOTS of different enclosures labeled as 1590B on the Internet. Make sure you check the measurements to make sure that the the size meets your required specs.
Our 1590B measures 112 x 61 x 31mm (4.4 x 2.4 x 1.2") and fastens with four screws.
1590B Hammond clone enclosure
With lid and four screws
Packaged in shrink-wrapped plastic
Depth: 31mm, including lid