I am reading the description of the [Mithral Golem](http://www.d20pfsrd.com/bestiary/monster-listings/constructs/golem/golem-mithral/) on d20pfsrd.org. In the description of the *Quickness (Ex)* special ability, it states:

> A mithral golem is incredibly quick. It can take an extra move action during its turn each round. This means it can move up to double its speed and still make a full attack.

This doesn't make any sense, since making a Full Attack would use Golem's full-round action, and the bonus move action left over would only allow it to move its normal speed, 50ft. So far as I can see the Golem does not have any other abilities which would allow it to move more. Why does the description state it can move up to double speed and still full attack?