Contemporary depictions, however, imply that Byzantine cataphracts were not as completely armored as the earlier Roman and Sassanid incarnation. The horse armor was noticeably lighter than earlier examples, being made of leather scales or quilted cloth rather than metal at all. Byzantine cataphracts of the 10th century were drawn from the ranks of the middle-class landowners through the "theme" system, providing the Byzantine Empire with a motivated and professional force that could support its own wartime expenditures. The previously mentioned term "Clibanarii" (possibly representing a distinct class of cavalry from the cataphract) was brought to the fore in the 10th and 11th centuries of the Byzantine Empire, known in Byzantine Greek as "Klibanophoros", which appeared to be a throwback to the super-heavy cavalry of earlier antiquity. These cataphracts specialised in forming a wedge formation and penetrating enemy formations to create gaps, enabling lighter troops to make a breakthrough. Alternatively, they were used to target the head of the enemy force, typically a foreign emperor.