To view a longer list of Amazon products click Preacher Curl Bench
There isn't much to a Preacher Curl Bench and some providers try and make you think their's is awesome and they charge you over $180, like the Valor Fitness CB-6 Adjustable Arm Curl Bench, don't let them convince you that you need that when you can buy the same Preacher Bench, excluding the adjustable arm, for a tad over $60.
When I was locked up in McNeil Island we didn't have a preacher bench, but there were some old barrels and 2x4's laying around so we made that work, it looked something like this:
They do make some preacher benches with other things like the leg workout and more. But like I said, don't let some scammer make you think you need something you don't need.