That's part of Outfitter.   It's a bar of icons for each of the outfits.  Optional thing, can hide it, rely on hotkeys or macros or drop down menus if you don't want it.  

Outfitter vs Itemrack, from my experience.

- More intuitive setup of outfits:   Open up your set, which is directly from your paper doll screen, equip the items.    Itemrack from what I can tell, open that in its own paper doll UI, pick a set or type in some new set, go through slot by slot, hit save (I forget to do that at times).     There's also some auto set building if you want in Outfitter, never used it often but can build sets based on the Highest AP, Stam, Shadow Resist, etc.   Saves you from looking through your bags if you know exactly how you want to build it.

- Automation:  Though theres events in Itemrack.  I never went in em too much.  Had to flip a page to search for what I want, I think sorted alphabetically.    Outfitter does classify the events, PvP, Activities, etc, so again easier to find and set up.   The thing I'm in love with atm is my Fishing set up.   If I'm fishing and I enter combat for whatever reason, out pops my warglaives automatically.  lol  

- Seperation of Full Sets and Partial Sets:   Though in Itemrack you can set up "empty slots" to make partial sets.   There's no indication of it really.   Just names/icons you give it.    Outfitter seperates them out and puts them lower.   Ease of seeing what you can mix and match.

Hmm can't think of anything else that's definitely different, haven't used Itemrack as much.

But some neat tricks.

- Designate each outfit to show/hide helm/cloak/title.    Can pick and choose which one you think it's ugly to hide, and match a title if you want

- Ability to deposit / withdraw all items of an outfit into a bank, or just the ones not used by any other outfit.

- Tooltip to tell you if item is used by any outfit(s)