Based on the Travelling Equipment - Feather Backpacks but any of the version should work.
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Credits and distribution permission
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File credits
PushTheWinButton for the mod: Travelling Equipment - Cloaks and Backpacks. Maskar for the mod: Maskar's Oblivion Overhaul Ph0rce for the mod: Travelers Cloaks. side777 for the mod Side_s Backpacks.
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Changelogs
Version 1.1
Changed Traveller references for Traveler. Added bash tags.
Integrates the 5 backpacks from Maskar's Oblivion Overhaul into the "Travelling Equipment - Cloaks and Backpacks" logic. This means, that Maskar's backpacks will be using the meshes from said mod and will also combine with the cloaks. In addition, these backpacks will be using the tail slot which will free the amulet slot, so now you do not have to choose between an enchanted amulet or your hoarder backpack.
I have also simplified the script to implement only the merging logic since I haven't had any issues with the enchantments from Maskar's backpacks and the logic seemed more straight forward and functional.
Additionally, I have made some changes to the naming of the backpacks and the combination of them. Instead of tiny, small, medium, large and huge. They will be "standard", traveller, adventurer, merchant and hoarded and the combinations will recive the name of "backpack set", "traveller set", "adventurer set" and so on.
Fell free to change on your own the names with xEdit if you do not like them...