
Please use the "backpack" permission in cause this permission is not working for you. Some permission plugins have problems with this permission.
e - Allows a player to open their backpack. If you are still using Java 7 you can use this version. (Optional) PCGF PluginLib ( Advantages of using the PCGF PluginLib). Bukkit, Spigot, Paper or Uranium for Minecraft 1.7.10 or newer. Preserves the NBT data of items (everything that can be stored in a chest can be stored in the backpack). Item filter (block items from being stored in the backpack). Multi language support ( multiple language file included). Multiple storage back-ends (Files, SQLite, MySQL). Shortcut item to allow faster interaction with backpack (can be disabled in the config). Auto item-collect on full inventory (can be enabled in the config).
Backpack size controlled by permissions.Minepacks is a free and reliable backpack plugin with different backpack sizes, fully customizable language files and MySQL storage support.