Don't wear the competitor's shoes to the interview.
Other than that, it's a manufacturing job. The position description may
clue you in to what you'll be doing. Cost accounting could be one, payroll
accounting, or sales tax, or regular accounting for the company, If you
know what position you're interviewing for, bone up a little on that topic.
Brush up on things like the various methods off accounting for inventory,
the UNICAP rules (section 263a), etc. Don't plan to WOW!!! them, as it
probably won't work. Just know a little bit about some of the goings on for
the position you are applying for.
Yes, as Paul says, whatever you do, don't plan to "wow" them. Just be
confident that you know the basics of accounting well enough to learn
what they need you to do, assuming they put at least some of the same
effort into you as you do into them. Try to get a feel for what the
training is like and if your boss is a nice person. That does matter.