(Clearwisdom.net)

These wooden shackles usually weigh 10 or 15 kilograms.
The illustration on the upper left shows what the assembled shackle looks
like. The picture on the lower right shows how the shackle is constructed using
two pieces of wood.
There are two holes about 30 cm apart on the shackle. The shackle is about 66
cm long, 33 cm wide and 6.6 cm thick. Its two parts are connected by a nut and
bolt. The nut is about 2.5 cm thick, and the bolt is about 56 cm long and 2 cm
thick.
The practitioners are forced to put their feet in the holes and then the two
parts are secured with the nuts and bolts. When they walk, they have to bend
down to carry the shackle and move forward bit by bit; otherwise the flesh on
their legs would rub against the wood. When they sleep, they're not allowed to
take off the shackle and must sleep on their backs.