A full plaid is a long piece of tartan fabric, traditionally worn as part of a full highland dress uniform. It usually matches the tartan of the kilt. A full plaid is pleated the whole way, with half of its length sewn shut (so that the pleats cannot open). Its length is almost twice the height of the wearer (about twice the distance from the ground to the wearer's shoulder).
A full plaid is typically only seen on members of pipe bands which elect to wear full dress (military styled) uniforms, and occasionally as formal highland dress.
The full plaid is wrapped around the wearer's chest and under right arm, pulled firm to the body. The plaid is twisted on the left shoulder with one loose end falling behind the wearer's back and getting tucked into the waist belt. The leading edge of the other loose end is pulled forward and draped over the wearer's left shoulder.