Studying this lesson, Environment War I troopers would deploy barbed wire in so-known as concertinas which were somewhat loose. Barbed wire concertinas can be geared up within the trenches and then deployed in no-male's-land fairly immediately beneath cover of darkness. Concertina wire, also known as coiled wire or concertina fencing, https://www.qunkunmetal.com/fencing/concertina-razor-wire.html