D&D 3E/3.5 [3.5] Adamantine Damage reduction

[hazmat]

Adamantine armor gives x/- damage reduction. Based on the category of armor. Light gives (1/-) , Medium gives (2/-) and Heavy gives (3/-).

Does this damage reduction stack with damage reduction granted by class abilities or feats?

I have a character in my campaign who has 4/- from feats and is looking to get adamatine heavy armor. It'll make my job a little tougher but the campaign *is* high powered.

I'm probably going to let it stack because it just makes sense to me. I'm just looking for what the rules say about this.

 

[Zerth]

Same type DR does not stack. Use only the one, that gives the best protection.