There is a series of these fighting knives first written about in 1990 by Major E.J. (Ted) Millett (MBE) whose extensive army career saw him finish as head of Australian Army Ordnance with one responsibility being the Small Arms Factory at Lithgow.
There are many blade varieties/shapes depending upon what part of the blade was used, however, the majority of the cast grips are the four finger type knuckle guard cast in aluminium with a very small number cast in brass, which are considerably heavier. The handles are all marked with D↑D 1943. (Reference KMS page 292 – full story pages 288-292).