These items allow agents and traders to get access to a pretty nice piece of headwear that is unique to their professions.
The trader hat is an Advanced Salesman's Hat and is aimed at levels 20-75. It is a leveling item that can be upgraded at each level by right-clicking on it up until its maximum level of 75. It good protection and Additional bonuses, specially Energy AC which can more then compensate for the lack of Energy AC in Carbonum Armor.
At level 75 it adds 5 to Computer Literacy and 20 each to your Nano and Nano Inits.
To make the Advanced Salesman's Hat you first need to travel to the outpost of Hope in Mort and purchase a Salesman's Hat from Zoftlig Blimp. Be aware that it costs almost half a million credits, so if you're low level it will probably take a chunk out of your pocket.
Now all you need is to find a Salesman Chip and this is the tricky part. It's a random drop from any trader mob between levels 20-75.
It's really just a matter of luck whether you find one or not. On the plus side the item is not NoDrop so you can buy them from other players. You need to have 125 in Electrical Engineering to be able to combine the chip with the hat, but traders have an apprentice nano line to buff that skill.