I think as a DM there are two ways you can use the shirt. 

1. Considered a medium Armor Chain Shirt it gives AC 13+ Dex (max.+2) but as a +1 AC it totals to AC 14+ Dex (max 2). I would recommend giving full Dex Bonus instead of max +2 because it's an "Elven Chain Shirt"

2. The description says between cloth or leather, so wearing it under any other Armor it gives just +1 as another layer of protection. So wearing a Leather Armor for example would give you AC 11+ Dex + Elven Chain +1 total AC 12, or a Platemail to Total of AC 19

just my 2cp

Though wearing a chain shirt under other armour is consistent with history, I just want to point out that the flavour text of this matches word for word with the normal, non-magical, medium armor Chain Shirt.

Wearing two different types of armor, even it were possible, would have no effect on your AC.

The rules state "The armor (and shield) you wear determines your base Armor Class." Different armors don't add anything. They would, again if it were possible to wear two sets which is another issue, allow you to chose from the two different armors when calculating base armor class.

So you would select one of the two armors for your base armor class. Then Dex etc add onto that.

You can't have two different base armor classes in effect at the same time. 

As to the question of whether you can wear two different sets of armor? IMHO that is ludicrous and plainly contrary to the intention of the rules. If you start down that path you will find yourself with players holding 4 swords in each hand, 3 cloaks two helmets etc. The game doesn't need people trying to wear two sets of armor at the same time and, aside from some half-baked attempt at power gaming, I cannot imagine why anyone would want to.

To many min-maxers. Obviously this is designed for halfing rouges to stop them dying from troll spears. 

But beside LOTR take, is better than mage armour, AC14.

Question should be does it work with bladesinging? This is where RAW is no due medium armour property, but head says yes, or way would elves bother..

Quote from BanishedAir >>

It specifically says that it's usually worn between layers of cloth and leather though. I imagine mechanically it would still be the same, but that sounds like it can be worn with other armour. 

 it might sound like it, but that's describing chain shirts in general. There's a thin layer of cloth or leather under the chain because it's just uncomfortable (and drafty) not to have a layer under it.

Chain shirts do not stack with other forms of armor. Armor in general does not stack, period. The leather layer under medium and heavy armor is considered part of the armor and gives no extra mechanical benefit.

Well druid could still use it, its just a taboo and players can talk to dms to allow it. Its not a mechanical restriction. Though in my game I allow a druid to wear metal, but i will make it into a story element. Taboo against the spirits/guardians and god of nature in my setting.

Does this have the normal medium armor Dex bonus limit of +2? It would seem that Elves would not appreciate the Dex bonus limit.

I believe chainshirts can be work under clothing, so I don’t see why it couldn’t be worn under armor

My DM gave me eleven chain +3.  I want to incorporate into the character, but don't know how to change the stats of something already established as a magic item... please help.

Are you confused as to how you change something on your digital character sheet? If you are I would recommend overriding your AC just by tapping it and selecting a new value, it’s probably the simplest way to give yourself homebrew. After that you only need to add the chain shirt to your inventory and customize the Notes section so you don’t forget why you have that extra AC.

Quote from lmurdock >>

My DM gave me eleven chain +3.  I want to incorporate into the character, but don't know how to change the stats of something already established as a magic item... please help.

 

 

Beyond 20

 

 

 

 

 

 Are you confused as to how you change something on your digital character sheet? If you are I would recommend overriding your AC just by tapping it and selecting a new value, it’s probably the simplest way to give yourself homebrew. After that you only need to add the chain shirt to your inventory and customize the Notes section so you don’t forget why you have that extra AC.

But what Metal / Material is it MADE FROM!?!

what's the normal ac?

Historically, you don't wear chain mail beneath plate mail (if that helps!). As a DM, I'd definitely say no to that one.

 Seems pretty pointless for a Dex/stealth based char if the max Dex AC bonus is still 2.

Seems like a fair number of people are complaining about a niche item that isn't for thier niche.  This isn't for high Dex characters, & it is only 1 AC better than Studded Leather, not a big deal.   This is for characters without Medium Armor proficiency that don't prioritize Dex, like Warlocks, Sorcerers & especially Wizards. It's improved Mage Armor that can't be dispelled.

Quote from BobTheSkull13 >>

Quote from nitrox3690 >>

Can spellcasters use it?

 Yes. Though not druids because it is metal.

 Druids are fully capable of using metal. Most just choose not to.

Ugh, this item which used to be a staple in the game is now useless unless you are playing a wizard or sorcerer. Even rogues are better off with regular studded leather instead of this item. And then its a Rare magic item? "Rare" as in it is rarely needed.

That's really up to the dm as to the "why" it works, don't you think. As a dm, I'd personally go with the mithril craftsmanship idea.

I used to think this was perfect for my elven rogue first character ever. But now I realise in the long run, studded leather would be better purely for the fact that there is a dex limit on medium armor (badly made mechanic). Soo, someone correct me if im wrong, but studded leather is better