Concertina Barbed Wire
Concertina barbed wire is a tape of barbed wire that is formed in large coils which can be expanded like a concertina instrument, each coil actually consists of two oppositely wound helices which supports each other against crushing while allowing easy longitudinal movement, the concertina wire packs flat for ease of transportation, but can very well be deployed as an obstacle much more quickly than the ordinary barbed wire, it is mainly used in the very high-security area to deter trespassing men and animals.
