I have this neck in my vault as a 304 item Choker of Barbed Reins from karazhan and in the tooltip is says: Tanking damage has a chance to instantly deal 72 physical damage to nearby enemies.
But if i look into the journal and search for the neck on attumen in lower kara it deals exactly the same amount of damage at level 50. wtf
There’s a bug with quite a few vault items, namely that some WoD items are showing as level 51 rather than 304. This might be a similar issue, where they haven’t scaled the item properly