The lower load of the Mark 4, yet in the same tube as the Mark 5, makes them Ideal for when your site has noise-conscious neighbour, now in a smaller tube which is ideal for fitting in your webbing.
When the 7 second fuse burns down the result is still a loud bang and a bright flash more ideally suited for built up areas. Each comes with robust and reliable twist and strike cap ignition system that protects the fuse from damage or accidental ignition.