The backstrap loom, in use before European contact and still used by some weavers today, cannot even exist on its own without the support of a convenient upright at one end and the weaver's body at the other. The weaver controls the tension by the direction in which she moves her body, and opens and closes the sheds in which weft threads are inserted by lifting heddles, placing and rotating the wooden batten, and using other hand-held implements as needed… 'The loom itself appears to be a simple device. When the cloth is completed, nothing remains of the loom except a pile of sticks', yet studies of this technology have argued that it is really 'a complex device, more responsive to the weaver's creative impulses than the modern treadle loom' introduced into the region by the Spanish.