Agave Filifera is also known is the Thread Agave. It's an evergreen perennial growing up to 45cm, with compact rosettes of rigid, pointed leaves edged with long white fibres.
The perfect addition for your outdoor succulent collection. It looks incredibly ornamental in either a planter or rockery. They're happiest in full sun and with lots of grit for sufficient drainage.
The pot size is 10cm.