File:US Navy 090320-N-8574M-034 A Seabee assigned to Naval Mobile Construction Battalion (NMCB) 5 lifts concertina wire to complete a section of a triple-strand protective barrier.jpg - Wikimedia Commons
Concertina wire - Wikipedia
Concertina wire - Wikipedia
Razor Wire Vs Barbed Wire (The Most Detailed Comparison) - Dongfu Wire Mesh
Razor Concertina Wire Supplied to Enhance Security