There are several types of panels, with different functions. Each panel must be installed in a grid in order to take effect. The grid begins with fifteen open slots, and additional slots are unlocked by obtaining Slot Releasers. There can only be one weapon panel and one ring panel installed in the grid at one time, and multiple ability panels cannot be installed with the same name; otherwise, the panels that can be installed are restricted only by the size of the grid and the size and shape of the panels.
Some panels take up multiple slots. These panels have link zones, where certain panels can be placed to "link" with the main panel for additional effects. For example, Doublecast ④ occupies four slots in the grid, including a link zone that covers three slots, in which magic panels can be installed. Each magic panel in that link zone will grant two casts of its respective magic during missions.
A Slot Releaser (スロット開放, Surotto Kaihō?) is a single-use item that unlocks an additional slot in the panel grid. It is automatically used immediately after it is obtained.
There are 105 Slot Releasers that can be obtained, bringing the grid to its full 120 slots.
List of Panels
Item Panels 
Item panels, when installed, provide consumable items at the start of a mission. These items are separate from the backpack, which has a limited capacity; there is no limit to the number of item panels that can be equipped. If the item is consumed during a mission, the panel is consumed, as well.
Support Panels 
Support panels have three types, one which raises the character's level, and one which increases the amount of items that can be picked up from treasure chests or enemy drops during a mission. The final type unlocks characters and modifiers to Mission Mode and does not appear in the inventory.
Magic Panels 
Equipping magic panels allows magic to be used during missions. Basic magic panels may be installed individually to grant a single cast of magic each, or they can be placed in the link zones of special magic panels, either granting multiple casts, or increasing the potency of the magic. The effects are cumulative: for example, linking one Fire panel to Doublecast and two to Magic LV2 will grant four casts of Fire LV4, while linking two Fire panels to Triplecast and one to Magic LV3 will grant seven casts of Fire LV3.
Magic panels are not consumed when magic is cast. Used casts can be replenished by using items like Ethers or Elixirs.
Ability Panels 
Installing ability panels activates corresponding abilities. Some abilities can be activated by multiple panels, with the difference being the size of their link zones, but only one panel can be installed for a single ability. Many ability panels have associated link panels that level up the main panel's associated ability or provide additional abilities. For example, linking Glide LV+ Ⓛ and Homing Glide Ⓛ to Glide ③ provides the Glide LV2 and Homing Glide abilities.
Weapon Panels 
Weapon panels modify a character's weapon, with Gears changing it to a new form, with unique attack combos and stats, and Unit link panels further boosting stats and unlocking abilities. While each weapon has a different set of stats, groups of gears will provide weapons with similar stat balances. Each playable character's weapon will be affected by Gears and Units differently. Only one Gear can be equipped at a time.
Ring Panels 
Material panels cannot be installed in the panel grid. Instead they are used at the Moogle Shop to synthesize other panels.