This is an old hand-knitted back pad called a mino or bandori from the north side of Japan.
 
It was used as a cushion between the back and the baggage when carrying heavy objects or as a place to lay down and rest for farmers.
 
In the old days, Japanese farmers used to work at home during the winter when they did not have to work, doing straw crafts for farming and daily life.
 
This one was made from shredded cotton kimono and rice straws. This one considering haven't been used, is in good condition to display. But please note that fine debris from the straw will fall out if you shake it hard.
 
Mesures : 117cm (46") × 32cm (12")