This pair is usable for pendant top or earring and pias parts, since there is a hole at top area for each. Size is 8.73mmx20mmx5.91mm for each. the hole is about 1mm(diameter). Please check another version, which has two holes at top and bottom, to connect each or other parts for your own jewelry. Another version's product name: twist pair parts 2 hole. The volume is approx 107 cubic millimeters for each. It would be about 1.07g for staring siliver (for each).