rigging sling(s). usually with at least one spliced eye and a Prusik to position the load line. Used to rig a tree limb in a balanced configuration. not allowing either end to drop.
Merriam-Webster Online Dictionary
balancer (noun)one that - balances , specifically - haltere
balancer (Wikipedia)
Balancer are a hybrid breed of beef cattle, a combination of Gelbvieh and Angus. These cattle are bred for their hybrid vigour, resulting in a higher growth rate and better quality meat.