The shotgun pictured here is a Spas 12 Gauge shotgun, made popular in the movie "Terminator".
Type: selective pump-action or gas-operated
Gauge: 12
Length: 1041mm
Barrel length: 546mm.
Weight 4.4 kg
Capacity: 8 rounds in under barrel tube magazine
This is specially designed police/military shotgun. Ability to switch from gas to manual pump operation allows use of low-energy non-lethal ammunition or unreliable (i.e. wet) ammunition that can cause misfires. Very popular along the different Law Enforcement agencies and security services.