This is a practice Bakelite charge holder for the German Teller Mine 35 for the German Wehrmacht T.Mi35.  This is a very hard to find item.
This is inert and was used for practice only.  The holder went inside of a Practice Tlllermine 35 and had small charges for making smoke.
This is a original WWII issue training aid and is not a real mine nor can it be made into a real mine.