Chest harness
A rope harness on the chest that does not bind the arms; Shibari Study gives munenawa as its Japanese name, and Rope365 also lists shinju.
Chest harness is the English term for a tie on the chest that leaves the arms free. Shibari Study defines it as any harness applied to the chest without including the arms and gives munenawa as the Japanese name, while Rope365 lists both munenawa (chest rope) and shinju (pearl) as synonyms. The arms mark the difference from a box tie, which Shibari Study defines as an upper-body tie with the arms behind the back, combined with wraps around the chest.