The tracer weighs 10 1/2 drams. and consists of a steel tubular body, brass tubular liner, tracer and priming compositions, steel closing disc, metal foil disc, and a metal washer. The steel components are rust proofed.

The body has an overall length of 0.94 inch and a maximum diameter of 0.59 inch, and is screwthreaded for insertion in the base of fuze Bd.Z. 5103*.

The tracer composition is grey in colour and weighs approximately 34 grains. It consists of barium nitrate 63.4 per cent, magnesium metal 31.5 per cent, and resinous matter 5.1 per cent. The composition is pressed with a spigoted drift into the brass liner before in-sertion in the tracer body from the front.

The front of the tracer is closed by turning the end of the body over the chamfered peri-phery of the steel disc and sealed by a thin coating of black paint.

The priming composition is grey in colour and weighs approximately 21.6 grains. It con-sists of barium peroxide 79.3 per cent, magnesium metal 19.5 per cent, barium nitrate 1.2 per cent. The composition is pressed into the body from the rear by a serrated drift after the liner with tracer composition has been inserted. The rear of the tracer is closed by a metal foil disc held by pressing a metal washer into an undercut recess.