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These solid plastic dummies shown below are meant to be used with TMA mines, for training purposes.
The top row was to be used with the (practice) VTMA-3 and VTMA-4.
The lower row were to be used with the (live) TMA-3 and TMA-4.

Using these dummy fuzes on live mines makes training more dangerous in my opinion.
Does anyone know how this was instructed ?

Photos © M. Jochoms.