Stalwart [5+]

Model has 1 additional Wound. This does not count towards unit size.

The extra wounds trait in the common category is further restricted; up to half (round down) of your models can have 1 extra wound, and up to half (round down) of those can have 2 extra wounds. e.g. in a tacteam of four models you can max have one model with 3 wounds and one with 2 wounds.
This does not include traits such as Ablative Armour.