Other ranks cap badges with blades

[Sonofacqms]

I have recently seen some other ranks cap badges with blades, in the past I have had the odd one, Australian General Service springs to mind but there seems to be several line Regiments with this type of fixing around.

Is this likely to be another ruse by the fakers to sell dodgy badges or is there a chance blades were actually fitted to bi-metal cap badges?

Your thoughts appreciated.

Rob