6.3mm Round x 2.1mm wide x 2.3 tall or deep. These are solid copper. They are old molds. They are hard to find nowadays, these are folded perfectly, into a rectangle box with an edge opened. These can be used to finish off a end of wire for example and soldered on. These are very fine and tiny.
B-007, Type of Metal - Copper, , Grade of Metal - First Grade, , Gauge of Metal - 30 Gauge, , Measurement - 6.3mm long x 2.1mm wide OD x 2.3mm tall, 6.1mm x 1.6 ID, Quantity - 10,