Kind of odd black composition pair here. The one on the left is a normal enough shape, but made of some sort of black composition material. It stands 4" tall. It is marked on top: LE/GPO/48. Embossed in a recessed circle. The one on the right is a 'dry spot' with a screw on cap. It has two wire lead holes beside the small British pin hole. It is marked on top: TR/GPO/^ [that is, an arrow pointing upwards] It stands 4 1/2" tall. Any thoughts on how common, or uncommon these two items are? Any information is appreciated. Yeah, I know the GPO is for Government Post Office.