What do they look like?

A collection of dummy explosives, detonators and fuses
© The Board of Trustees of the Science Museum

Firework Triangle Wheel, Brock’s ‘Crystal Palace’ Fireworks
© The Board of Trustees of the Science Museum

Railway line signalling detonator by Kynoch
© The Board of Trustees of the Science Museum

‘Selfac’ self-acting automatic fire extinguisher by F.E. Proprietary Co. Ltd
© The Board of Trustees of the Science Museum

Howitzer shell marked INERT
© Imperial War Museum

Brass letter opener with handle made from cartridge ammunition
© Imperial War Museum

German incendiary bomb, World War II
© Museum of London